First slide

Rate Measure

Question

The side of a cube increases at the rate of 0.01 cm/sec. The rate of increase in the surface area of the cube when the side is 4cm is

Moderate

A

0.38 sq. _{$c m / \sec$} .
B

0.48 sq. _{$c m / \sec$} .
C

10 sq. _{$c m / \sec$} .
D

15 sq. _{$c m / \sec$} .

Solution

_{$\frac{d x}{d t} = 0.01$}
        _{$s = 6 x^{2}, x = 4$}

        _{$\frac{d s}{d t} = 12 x . \frac{d x}{d t}$}

        = _{$12 \times 4 \times (0.01)$}

        = _{$0.48 s q . c m / \sec$}

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App