Operations on Functions-Division

[@anisha278]

when you can't understand your lesson in your online class, so you go here instead

[@mathematechxblackboard1942]

If you have math problems you can't solve, you may post it too by replying here. I may not be able to answer all questions posted(1 question per person per day), but I will find time to share my knowledge. :)

[@zeinamrican601]

@@mathematechxblackboard1942 thanks Your follower from Syria in the middle east

[@marklumauig]

@@mathematechxblackboard1942 how to solve f(x)/g(x) given f(x)=15x¹⁵ , g(x)=3x⁹?

[@marklumauig]

@@mathematechxblackboard1942 how to solve f(x)/g(x) given f(x)=15x¹⁵ , g(x)=3x⁹?

[@mathematechxblackboard1942]

@@marklumauig ​ @kram Hi! f(x)/g(x)= 15x^15/3x^9 . As you can see, you have numbers and x with exponents. for the numbers(15 and 3), divide 15 by 3 so it's 5. for x^15 and x^9, this becomes x^6. From laws on exponents, whenever you divide x containing exponents, subtract their exponents. Hence, x^15/x^9 means x^(15-9), so it's x^6. Therefore, the answer is 5x^6.

[@kuonnkaminie3697]

I'm in modular class I don't even understand a thing thnx for all the video who looks like this

[@junnediaz2278]

Yow same here HAHAHA just keep it together we will get through this

[@junnediaz2278]

@p s it's basically like test papers but thicker and more complex, it's like a self teaching book and it's way harder trust me HAHAHAAHAHHA

[@denniscuesta7009]

Thanks bro, you saved me from breaking my head against the wall Floor gang member is pleased

[@kamochidhahe]

8:56 the negative two x squared - positive 9 x squared why your answer is negative 11x squared it supposed to be positive 7 x squared right?

[@rexrommelgerarcas932]

Same thought

[@dheasacro7869]

hays tatambay na nga lang dito pa talaga

[@oiboi1893]

Tbh i usually get stuck at the breaking down part

[@ashley2819]

i just finished watching the video and boi i thought u were pertaining to breaking down ~ mentally ~ 😭😭😭😭 but i agree with u lmfao

[@ericzonmadarang7729]

8:11, -2x²+9x² is equal to -11x² I think it was wrong it should be 7x² because, the rule of addition and subtraction when it comes to sign is different sign subtract and copy the biggest sign.

[@mathematechxblackboard1942]

Hi! it should be -2x^2 - (+9x^2) so it become -2x^2-9x^2 so it is really -11x^2.

[@ericzonmadarang7729]

@@mathematechxblackboard1942 Ah okay I get it.

[@AstraDokja-cu8qo]

Why is -2x^2+9x^2= -11x^2? Shouldn't it be "7x^2"?

[@Georgiaa-l9k]

How to know if the function is not factorable? If it is not factorable mean you dont have to solve the problem?

[@kyoshi2239]

the denominator's result can't be 0, if it became zero, it isn't possible for it to be factorized

[@ansarm350]

You explained very well.thank you

[@ewunetumerera9388]

Thank you so much, but I still feel that there is a simplest way to divide high degree polynomials in to factors of binomials .

[@rentsuso4671]

I found out that your voice sounds like the one who was teaches us gApps in Apec. This school year po.

[@movieedition1878]

-8+ 114 is equals to 106 right??? not -122?

[@mathematechxblackboard1942]

Hi! You should be subtracting the two numbers, hence, it should be -8-(+114)=-122. I should have made it like this to make it clear: (38x-8)-(38x+114) =38x-8-38x-114= -122

[@ishaanarya7408]

Great explanation. Thank you

[@malacadjohnlhorenza.1714]

Thnx much sensei

[@dennisgono208]

How about this sir p(x)= 2x² + 5x - 3 ; if p(x+1) "evaluating function"

[@mathematechxblackboard1942]

place "x+1" to every x in p(x). hence, it becomes 2(x+1)^2+5(x+1)-3 and simplify. copy and paste 2(x+1)^2+5(x+1)-3 in wolfram alpha(search in google or click www.wolframalpha.com/) to see the simplest form . Always remember, evaluation is basically substitution. so if it say p(z), change x with z. if it says p(2x), change x with 2x. it is always like this. just like numbers, when looking for p(2), you replace x with 2 and simplify.

[@johnpauloamadeo3290]

-2 + 9 = 7? But why is it -11 I'm confused.

[@mathematechxblackboard1942]

Sorry, I should have made it clear that it is -2 minus (+9). When you work on that step, the operation is subtraction. I should have placed the expressions inside the parentheses to make it not confusing.

[@lojy4513]

What would i do if they can't be simplified?

[@jean7064]

thank youuu it helps me a lot since i forgot this lesson in my gr 9 dayss

[@itsyourboiDiazo]

Sir can you point po sana kung anong nga number inaadd mo kase hirap din po kase kung sasabihin lang. Or add arrow po kung San Yung e aadd or e maminus. Ty

[@irisesmael5077]

how it become x-3/x+6??

[@angelagraham467]

What about a problem that says this... f(x) = x² - 8x + 15 and g(x) = x - 5 Find (f ÷ g)(x) and express the result in standard form

[@mathematechxblackboard1942]

Hi Angela! (f÷g)(x) means f(x)/g(x) so it is equal to (x^2-8x+15)/(x-5). Factor numerator and you get (x-3)(x-5)/(x-5). cancel both (x-5) and you get (x-3). You could also use long division but not entirely needed as it is easier to factor in this case. Use long division only for cube and up.

[@angelagraham467]

@@mathematechxblackboard1942 Thank you! I actually got that answer but wasn't feeling confident in how I got there so until you verified it I was unsure. You just helped me lots!

[@keithrinaorlanda4526]

If the g(x)'s first term is a negative, do I need to change it to positive?

[@mathematechxblackboard1942]

Hi Keithrina! What do you mean by that? Can you give me a specific expression so I would better understand your question?By the way, are you from Pangasinan? Your last name is a common name in a place in Pangasinan.

[@keithrinaorlanda4526]

I encountered a problem in division of function wherein, x²+3 is fx, and -2x+6 is gx, but when it was substituted in the formula fx/gx, -2x+6 became 2x+6. P. S I'm not from Pangasinan😅

[@peony8928]

KZbin is OurTeacher

[@bernardinobathan7759]

If the teacher ask to simplify i will use the synthetic right?

[@mathematechxblackboard1942]

Bernardino bathan , yes and note that synthetic division is best to use when the numerator is a polynomial and the divisor is a binomial. If the expression is easy to factor in the numerator, like trinomials, then use factoring first.

[@jannahbuenavista4812]

This will help thanks a lot

[@sandradelara1854]

Hello! I need help with something. g(x)/f(x) f(x)= 2x-3 g(x)=5x-1 It also asks for the restriction for x?? Thank you! :’)

[@mathematechxblackboard1942]

Hi! Follow how it is written. It says f(x)/(g)x so form the fraction as 2x-3/5x-1. The restriction is based on the denominator 5x-1 as it cannot be zero. Zero denominator is undefined. Think of what number will make 5x-1 equal to zero. I know you can find this. Solve 5x-1=0. The answer to this is the restriction.x cannot be equal to what makes 5x-1 equals 0.

[@sandradelara1854]

@@mathematechxblackboard1942 Thank you so much for your help!!

[@sofiabautista2945]

How about x+2/ x-2 ??

[@mathematechxblackboard1942]

Hi! That is already the simplest form. No division needed.

[@Lazzhaa]

Thank you, I was really confused lol

[@dinapilapil1560]

Need help! g(x)=2x²+5x+2 h(x)=2x²-5x-3 Find (g/h) (3)=? Please help me!

[@mathematechxblackboard1942]

Hi Dina! Can you rewrite the g(x)? What is the sign between 2x^2 and 5x? Plus or minus?

[@dinapilapil1560]

It's +

[@mathematechxblackboard1942]

set up g/h then substitute 3 on both then simplify the value. That is 2(3)^2+5(3)+2 over 2(3)^2-5(3)-3. Answer is 35/0 or undefined since denominator cannot be 0.

[@dinapilapil1560]

Thank you so much😘😍

[@dinapilapil1560]

@@mathematechxblackboard1942 can you help about this.. What is fuction model of this condition.. 1.Twice the square of a number?

[@JovannyMaquilan]

5-33 = 38? bakit po naging 38? diba dapat -28 po?

[@leamortonvaldez596]

I was also confused like you do on that part but here: If two numbers have the same sign, either if its same negative or same positive, the answer will always be positive. So, -11×-3 = 33 To simply understand, same sign = positive answer Different sign = negative answer

[@mathematechxblackboard1942]

Hello. In my solution, naka indicate 5- (-33), so that is the same as 5+33, since the "minus negative" turns into a "plus". Basta lagi tandaan, kapag long division, you subtract so careful sa pag subtract ng negative number. I hope I answered your question. Sorry for late reply.

[@dungeonquest8210]

Paano ho nangyari na -2 + 9 = -11? tapos (-) pa e di ba ho (+)positive dapat na yung 11 kasi greater value ang 9 sa 2? tapos po +5x at -33x = 38x? bakit po positive na siya e di ba dapat negative yun at magiging subtraction yon at ang answer ay magiging negative since bigger than 5 ang 33?

[@mathematechxblackboard1942]

the default operation is subtraction, hence it should be -2- (+9)=-2-9=-11 and +5x - (-33x)=5x+33x=38x.

[@rexrommelgerarcas932]

I came to the comment section to see this thank u i understand it kudos ⚪​@@mathematechxblackboard1942

[@bernadetteedol4643]

Modular learning. I understood nothing. Had to search on KZbin. Thank you.

[@saito-qr4wu]

Sir pano po naging positive 38?

[@Ayieeen16]

How about if the f(x) is a fraction and also g(x) is a fraction too?? Thank you, hope mapansin.

[@mathematechxblackboard1942]

Hi Heaven! Could you give me a specific set of functions that you want to see? I will work through the exact functions that you will give me. Thank you.

[@Ayieeen16]

@@mathematechxblackboard1942 (f/g) (x) when f(x) = 4x/ 3x - 2 and g(x) 1/x also what if the f(x) = 1+1/x and g(x) =x

[@mathematechxblackboard1942]

@@Ayieeen16 Hi! I hope this one will help you understand the idea. kzbin.info/www/bejne/qHjYZGSYbNWFp5Y

[@Ayieeen16]

@@mathematechxblackboard1942 thank you po😭❤️❤️❤️❤️

[@vent1111]

hello there, may i ask, how do you divide f/g(-1) if f(x)= 6x^3 + 23x^2 - 8x - 7 and g(x) = 3x - 2 i've been stuck on this question for almost an hour :'))

[@mathematechxblackboard1942]

Hi! Do you still need to find the answer for this? Sorry for the late response.

[@vent1111]

@@mathematechxblackboard1942 I'll prolly just use it for reference but it would be nice :DD

[@mathematechxblackboard1942]

@@vent1111 , for this one, since it says (f/g)(-1), which means you are finding the value of f/g when x=-1, you can go straight to substituting -1 on the x of each function, f and g. So find f(-1) and find g(-1) then divide the resulting values. f(-1)=18 and g(-1) = -5 so the the value of (f/g)(-1)=18/-5 or -18/5.

[@almadinjohnchristophers.9014]

I hope you cans solve problems with only 2 expressions

[@mathematechxblackboard1942]

Hi Christopher! You may type in an actual problem that you need to understand how to answer. Thanks!

[@exuquseme3056]

How do i solve this? Find (f • g) (x) and (g • f) (x) f(x)=x , g(x)= 1/2x+1

[@mathematechxblackboard1942]

Hi! is this multiplication or composition? Just to make sure.

[@exuquseme3056]

@@mathematechxblackboard1942 it's multiplication

[@exuquseme3056]

Oh, my bad it's composition

[@mathematechxblackboard1942]

Hi! Here is a similar problem kzbin.info/www/bejne/fYTWk2VpnqeXa7s.

[@streamermode5224]

wrong answer on long division try seeing the signs first thats why many students got wrong becuase they dont go to see the signs if it is positive or negative

[@mathematechxblackboard1942]

please check it again. I think there is no error. :)

[@lesliesoto8352]

Thank you

[@RenjuAvellaneda-t4v]

Huh? Factoring 6 is 3x1? Lol

[@mikeyml7782]

3:08

[@neilaldwingregorio4282]

wow! for the first i can actually understand math hahhaah

[@jishu1743]

How about this sir: f(x)= 2x³ + x - 3 g(x)= x - 1 g(x)/f(x) With domain po

[@mathematechxblackboard1942]

Hi Samu! Just to be sure, is this 2x^3+x-3or 2x^2+x-3?

[@jishu1743]

@@mathematechxblackboard1942 2x^3 + x - 3 po

[@Palo_Azul]

F(x)= 3x+8 and G(x)=3x²+2. Find G(4)/F(4).

[@mathematechxblackboard1942]

here :) kzbin.info/www/bejne/j5S4ZXZ6mreHgrc

[@Palo_Azul]

@@mathematechxblackboard1942 Thank you for getting back to me!!! In my haste I realized what I was doing wrong! I realized I was adding the 16 and 3 and not multiplying it!

[@mathematechxblackboard1942]

@@Palo_Azul You're welcome. :)

[@charlenecortis3505]

Hi po...uhmmm I can't get the answer of this problem po..(j/g)(-1)

[@charlenecortis3505]

J(x)=x³+8 and g(x)=x+2

[@charlenecortis3505]

Need ur help po😓

[@mathematechxblackboard1942]

Sorry for the late reply. (j/g)(-1)=j(-1)/g(-1)= ((-1)^3+8)/(-1)+2=7/1=7. But if you are looking for (j/g)(x), you have to write the expression (x^3+8)/(x+2) which you still have to divide(or use factoring) to simplify.

[@jashleicanarias8149]

need help!! who knows the answer here: it is division btw f/g (x) f(x) = 3x-2 g(x) = x^2 + 2x - 3 i dont understand it lmao iT reAlly hUrts

[@mathematechxblackboard1942]

f/g x= (3x-2)/(x^2+2x-3) = (3x-2)/(x+3)(x-1)

[@chriseljohndelacruz9763]

How come -2+9 became -11 lololol explain

[@mathematechxblackboard1942]

Because it is subtraction, not addition. it shoud be -2-(+9)= -2-9=-11

[@vellomeilldulaca219]

thanks😢

[@cesjessuke7339]

sir, how about this? F(x)= x^2 + 3x + 2 G(x) = x + 2 1. (F/g) (3) ~ F (x)/ G (x) = F (3)/G (3) So... 3^2 + 3 (3) + 2 / 3 + 2 Ano po sagot po?

[@mathematechxblackboard1942]

perform PEMDAS and the answer is 4.

[@cesjessuke7339]

@@mathematechxblackboard1942 Tama ako hehe🙃 thank you pooo~~~

[@kuonnkaminie3697]

Bruh need help (F/g)(x) F(X)=4X - 6 G(X)=2X + 8

[@mathematechxblackboard1942]

factor out common factor for each function. 4x+6=2(2x+3) while 2x+8=2(x+4) so f(x)/g(x)= 2(2x+3)/2(x+4) then cancel 2 and 2 (numerator and denominator) result is (2x+3)/(x+4). Don't cancel "x". It is not allowed. okay? sorry for late reply.

[@latiffaraniaofficial0406]

Sir gdpm po paki help naman po kasi kanina pa kami nah solve hindi makuha namin.....isang mumber na hindi namin masagot ito po g(x)%h(x) given g(x)=x+3 h(x)=4x-8

[@mathematechxblackboard1942]

Mary Jane Janiola hi! From how I understand your question, the answer is (x+3)/(4x-8). That is the simplest form. I am curious why you found it confusing.kindly explain your confusion.

[@latiffaraniaofficial0406]

@@mathematechxblackboard1942 sir opo pero confusing po.....sir I try to solve but im not sure kung tama po ito.....please correct me if im wrong.....ito po ang solution ko.... given=g(x)=x+3 given=h(x)=4x-8 answer: x+3/4(-8) =x+3/4(x-2) yan po Sir Pablo ang sagot ko.

[@mathematechxblackboard1942]

@@latiffaraniaofficial0406 yes, that is correct. by the way I am not sir Pablo. :)

[@kirkkong5829]

Pinalitan yung example kase di masagotan HAHAHA

[@mathematechxblackboard1942]

I showed different cases. Some expressions are needed to be simplified, some can be written as is. And as a student, you should be able to identify these cases.

[@ognayonnapoleonjr.u.9688]

Wala ako naintindihan pota

[@zenmafia7942]

LU2 BOYSS PISOT

[@RomalynPilar-qr1uf]

Pa send po ng sagot

[@justinedelacruzcrisostomo8176]

I don't understand you

[@mathematechxblackboard1942]

You may ask other questions instead and I will try to explain how to answer it.