LRDI Maxima/Minima

[@CatpreparationiQuanta]

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[@AnshuKumar-oj8ww]

Last one can be solved much quickly without even using shreedharacharya formula. We know x=13/4 gives maxima, and just before this value and just after this value both the profit value are same as the equation is parabolic. So 13/4=3.25-2.8= 0.45, adding this to 3.25 we get 3.7. So number of boxes = 370

[@sufiyanadam]

bro drugs liya hai kya? 280/100 must be a root (2.8) and since it is a quadratic equation, it has another root as well, which we can know from the sum of roots equation; -b/a, A + 2.8 = 13/2 => A = 3.7 and it is equal to the number of box therefore the number of pieces would be 3.7x100=370.

[@AnshuKumar-oj8ww]

​@@sufiyanadam280/100 kiska root ? Drugs tune li h The line which crosses the quadratic equation at 2.8 will cut the eqn at yet another point which is point of maxima(x coordinate) + distance between maxima and 2.8. Maxima is 13/4 Ye bhi correct kar. Btw i've converted IIM C and B, A FABM and FMS, dont wanna boast this fact but FYI still.

[@sufiyanadam]

​@@AnshuKumar-oj8ww Translation: I don't wanna boast but I can't help the urge to tell someone the college I have done my master's from even though it has no relevance, but I like the validation that it gets me. 🃏 "The line which crosses the quadratic equation at 2.8 will cut the eqn at yet another point" Exactly and that line is the x axis. 280/100 = 2.8 which is the root of the quadratic equation for profit: -2x^2 + 13x - 9. The other root of this equation is the number of box (the other box) and multiply that by 100, you get the number of pieces in that box. We can solve this part quite easily; We know that sum of roots of quadratic equation is -b/a, also it is given that one root of this equation is 2.8, apply the formula here and you will get 3.7 as the other root.

[@ishantgupta7360]

@@AnshuKumar-oj8ww congratulations on conversion to these colleges! If possible , could you please tell me best resource to pratice lrdi set?

[@mananshah7095]

In the first question it should be mentioned as for how many values of pieces and not x since x is no. Of boxes

[@pradiptonag325]

Sir, why in the first question we have to multiply by 100 ?

[@ApoorvVerma]

sir, in 2nd question you wrote the values of x which were in underroot form into decimal.. how to estimate the correct decimal value of such rt. terms????

[@mihirmithaiwala1444]

In the 2nd question,you have multiplied by 100.In that case,we have to assume that the value of 1 piece is equal to 1rs???

[@astitvaapni6205]

Bhai in first ques where +1 comes from in the last calculation

[@CatpreparationiQuanta]

@@astitvaapni6205 when you have to find out number of terms from a to b then it is b-a+1 . for example number of terms from 2 to 10 is (2,3,4,5,6,7,8,9,10) i.e 9 terms which can be directly calculated by 10-2+1=9

[@CatpreparationiQuanta]

cost and revenue are in hundreds ...it is given in the question.. so profit per box will also be in hundreds so multiply it by 100...read the 4th line

[@Suhail_MS]

​@@CatpreparationiQuanta 571-79+1 = 493 , which will include both 571 and 79 where sales = cost ... ???

[@Suhail_MS]

So to find the values of x between, for eg: a nd b , it will b - a -1 right ?

[@souryabanik5578]

Hi

[@harshranjan8507]

sir is this set level equivalent to cat??

[@CatpreparationiQuanta]

Yes ofcourse

[@gaurabdeb1511]

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[@gaurabdeb1511]

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[@gaurabdeb1511]

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[@gaurabdeb1511]

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[@gaurabdeb1511]

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[@gaurabdeb1511]

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