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Ex 6.2

Ex 6.2, 1

Ex 6.2,2

Ex 6.2,3 Important

Ex 6.2,4

Ex 6.2, 5 Important

Ex 6.2, 6 (a)

Ex 6.2, 6 (b) Important

Ex 6.2, 6 (c) Important You are here

Ex 6.2, 6 (d)

Ex 6.2, 6 (e) Important

Ex 6.2, 7

Ex 6.2,8 Important

Ex 6.2,9 Important

Ex 6.2,10

Ex 6.2,11

Ex 6.2, 12 (A)

Ex 6.2, 12 (B) Important

Ex 6.2, 12 (C) Important

Ex 6.2, 12 (D)

Ex 6.2, 13 (MCQ) Important

Ex 6.2,14 Important

Ex 6.2,15

Ex 6.2, 16

Ex 6.2,17 Important

Ex 6.2,18

Ex 6.2,19 (MCQ) Important

Last updated at March 16, 2023 by Teachoo

Ex 6.2, 6 Find the intervals in which the following functions are strictly increasing or decreasing: (c) â2đĽ3 â 9đĽ2 â 12đĽ + 1 f(đĽ) = â2đĽ3 â 9đĽ2 â 12đĽ + 1 Calculating fâ(đ) fâ(đĽ) = â6đĽ2 â18đĽ â 12 + 0 fâ(đĽ) = â6(đĽ2+3đĽ+2) fâ(đĽ) = â6(đĽ2+2đĽ+đĽ+2) fâ(đĽ) = â6(đĽ(đĽ+2)+1(đĽ+2)) fâ(đ) = â6(đ+đ) (đ+đ) Putting fâ(đ) = 0 â 6(đĽ+1) (đĽ+2) = 0 (đĽ+1) (đĽ+2) = 0 So, đĽ = â1 , â2 Plotting points on number line Hence, f is strictly increasing for â2 < đ < â1 & strictly decreasing for đ < â2 & đ > â1 Hence, f is strictly increasing for â2 < đ < â1 & strictly decreasing for đ < â2 & đ > â1