Using differentials, find the approximate values of the following:
Let us assume that
Also, let x = 36 so that x + Δx = 37
⇒ 36 + Δx = 37
∴ Δx = 1
On differentiating f(x) with respect to x, we get
We know
When x = 36, we have
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 = 1
⇒ Δf = (0.08333)(1)
∴ Δf = 0.08333
Now, we have f(37) = f(36) + Δf
⇒ f(37) = 6 + 0.08333
∴ f(37) = 6.08333
Thus,