range.......

IIT JEE 2015 Answers › Calculus questions › range.......

d range of d function 4{x}³-3{x}

#Mathematics #Calculus

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8 Answers

1

Akshay Pamnani ·2009-09-10 21:06:54

[-1/2,1)

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Lokesh Verma ·2009-09-10 22:08:28

take the derivative.. it is

12{x}²-3

this is zero when {x} = 1/2

at x=0, f(x) =0

x=1, f(x) = 1

x=1/2, f(x) = 4/8-3/2 = -1

so the range is -1, 1

another way was to put x=cos @

this is cos 3@ where @ goes from 0 to pi/2

so 3@ goes from 0 to 3pi/2

hence the same answer :)

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1

gaurav ·2009-09-10 22:51:19

d right ans. is (2,4)

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eureka123 ·2009-09-10 23:00:26

noo.. answer is (-1,1)

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1

Akshay Pamnani ·2009-09-10 23:54:03

calculation mistake
euri right answer is [-1,1)

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1

Akshay Pamnani ·2009-09-10 23:57:23

another method
observe graph of 4x3-3x in [0,1)

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gaurav ·2009-09-11 09:14:56

no dude am sure right ans. is (2,4)

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24

eureka123 ·2009-09-11 09:30:54

tell the source of teh ques then ..

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Your Answer

Basic Integral Calculus Operators Symbols Matrix Cases

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