Q. 9 A5.0( 1 Vote )
Using differentials, find the approximate values of the following:

Answer :
Let us assume that
Also, let x = 25 so that x + Δx = 25.02
⇒ 25 + Δx = 25.02
∴ Δx = 0.02
On differentiating f(x) with respect to x, we get
We know
When x = 25, 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 = 0.02
⇒ Δf = (0.1)(0.02)
∴ Δf = 0.002
Now, we have f(25.02) = f(25) + Δf
⇒ f(25.02) = 5 + 0.002
∴ f(25.02) = 5.002
Thus,
Rate this question :






















If y = sin x and x changes from to
, what is the approximate change in y?
Find the percentage error in calculating the surface area of a cubical box if an error of 1% is made in measuring the lengths of the edges of the cube.
RD Sharma - Volume 1The radius of a sphere shrinks from 10 to 9.8 cm. Find approximately the decrease in its volume.
RD Sharma - Volume 1