Find the approximate change in the volume of a cube of side x meters caused by increasing the side by 1%.

Given a cube whose side x is increased by 1%.


Let Δx be the change in the value of x.


Hence, we have


Δx = 0.01x


The volume of a cube of radius x is given by


V = x3


On differentiating A with respect to x, we get



We know




Recall that if y = f(x) and Δx is a small increment in x, then the corresponding increment in y, Δy = f(x + Δx) – f(x), is approximately given as



Here, and Δx = 0.01x


ΔV = (3x2)(0.01x)


ΔV = 0.03x3


Thus, the approximate change in the volume of the cube is 0.03x3 m3.


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