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Question

Answer 1

(1)

Step 1:

The equation is .

Differentiate on each side with respect to .

Step 2:

The values of and .

The derivative with respect to is .

Solution:

.

Answer 2

(2)

Step 1:

The area of the square is .

The side of the square is increasing at rate .

Let the side of the square is .

The area of the square is .

Step 2:

Differentiate area of the square on each side.

Substitute and in the above.

Therefore the rate of change in the area is .

Solution:

The rate of change in the area is .