Double integrals and area

[@daliaomar3223]

You're really great. My maths professor literally stayed more than 3 hours explaining this and we still couldn't get it while you did it in 10 min thank you so much

[@empirearena4024]

Sir how to calculate the area of a single tile by using double integration

[@Timothymukansi]

Thank you for explaining the limits of the internal integral. I'm so relieved and delighted now!

[@lioneri11]

شكرا دوكتور.... thank u Dr.Chris

[@DrChrisTisdell]

Can you solve the simultaneous equations: y = sqrt(x) and y = x? That should give you x=1. If you solve the simultaneous equations y = sqrt(x) and y = x/2 then you should get x=4.

[@shobhitrastogi9273]

What does this mean by int/int??

[@brandonmo2811]

so why is the integrand f(x,y)=1,and I thought a double integral gives us a value that is a volume

[@DrChrisTisdell]

brandon mo \int \int dA = \int \int 1 dA It can give the volume, too. It depends on what the graph of $f$ represents.

[@ifuato]

why is that the intersection points are at x=1 and 4??

[@aishwaryar1998]

Thanks for this great explanation sir

[@Trading_Disorder]

how do u get 1 n 4 in graph is it by assumption...??

[@willstout4813]

sqrt of x=x and sqrt of x=x/2

[@brandonxu9278]

could you elaborate, im not seeing how that is.

[@emergency.jergens]

What's that small video on the corner? It looks like a lecture but why is it there?

[@DrChrisTisdell]

Hi. It's me, but due to a mix up with the files, it doesn't correspond to this particular presentation. Please ignore it if you find it distracting.

[@DeepakSingh-hd1sf]

Can we solve this problem without dividing into two parts? if yes, then how will we consider the limits?

[@DrChrisTisdell]

+Deepak Singh Yes, it is possible. What do you think the limits would be?

[@Fightclub1995]

you can see that the first region is just the area of two triangles substracted. so that part doesn't need integrals to calculate the area.

[@florali8582]

Hey, sir~ haven't c u for a month! For @Deepak Singh question, I think I can use substitution, and by changing by u=y/x, v=x, and in integrate area, we just multiply with the d(x,y)/d(u,v), then work out the limit of u and v.

[@shobhitrastogi9273]

But why integrand function is taken as f (x, y)= 1? Why is tha so? Plz make my doubt clear Dr

[@DrChrisTisdell]

Shobhit Rastogi \int \int dA = \int \int 1 dA

[@shobhitrastogi9273]

Sorry I didn't get that.please can you explain it again dr. It will be very kind of you chris

[@sidrodriguez17]

thank u Dr.Chris

[@AlchemistOfNirnroot]

What do mathematicians actually do?

[@DrChrisTisdell]

+AlchemistOfNirnroot According to Jobs Rated: "Applies mathematical theories and formulas to teach or solve problems in a business, educational, or industrial climate." They also rate the job highly www.careercast.com/jobs-rated/jobs-rated-2014-ranking-200-jobs-best-worst

[@AlchemistOfNirnroot]

Dr Chris Tisdell I like maths being applied, it's probably why I want to go into physics.

[@DrChrisTisdell]

+AlchemistOfNirnroot it's great if you can make the mathematics "do" something. :-) Best wishes.