
Introducing your new favourite teacher - Teachoo Black, at only ₹83 per month
Ex 6.4
Ex 6.4, 1 (ii)
Ex 6.4, 1 (iii)
Ex 6.4, 1 (iv)
Ex 6.4, 1 (v) Important
Ex 6.4, 1 (vi)
Ex 6.4, 1 (vii)
Ex 6.4, 1 (viii)
Ex 6.4, 1 (ix)
Ex 6.4, 1 (x)
Ex 6.4, 1 (xi) Important
Ex 6.4, 1 (xii)
Ex 6.4, 1 (xiii)
Ex 6.4, 1 (xiv) Important
Ex 6.4, 1 (xv)
Ex 6.4,2
Ex 6.4,3 Important
Ex 6.4,4
Ex 6.4,5 Important You are here
Ex 6.4,6
Ex 6.4,7
Ex 6.4,8 (MCQ) Important
Ex 6.4,9 (MCQ)
Last updated at April 15, 2021 by Teachoo
Ex 6.4, 5 Find the approximate change in the surface area of a cube of side x meters caused by decreasing the side by 1%.Let side of the cube = x meters. Given Decrease in side = 1% = − 0.01 x Hence, ∆ x = −0.01 x Surface area of the cube = S = 6x2 m2 We need to find the approximate change in the surface area of the cube i.e. ∆ S Now, ∆ S = 𝑑𝑠/𝑑𝑥 ∆x = 𝑑(6𝑥^2 )/𝑑𝑥 ∆x = 12x (−0.01x) = − 0.12x2 Hence, the approximate change is 0.12x2 m2