nid help to slove these questions

ZaiDancerz SG

1.) The tangent to the curve y=px^3 at the point where x =2 passes through the point (1,-10). Find the value of p.

2.) The period, T seconds of a pendulum is given by T= 2*pie*square root (l over g) where l is the length of the pendulum and g is the acceleration due to gravity. If g is a constant ,find dT/dl .

wee_ws SG

Hi,

For Q1:

1. When x = 2, y = ?

2. dy/dx = ?

3. When x = 2, value of dy/dx = ?

4. Gradient of line joining the point where x = 2 and (1, -10) = ?

5. Now value of dy/dx = gradient of line, from which p = ?

For Q2:

1. Rewrite T as T = {2 pi (g)^-0.5} (l)^0.5, noting that the expression within braces is a constant.

2. Use the fact that the derivative of x^n is nx^(n-1), to find dT/dl.

Thanks.

Cheers,
Wen Shih

ZaiDancerz SG

so the ans for question1 is 2.5?

TrueHeart SG

so the ans for question1 is 2.5?

Hi ZaiDancerz,

That is correct.

Cheers.

wee_ws SG

Hi ZaiDancerz,

Getting acquainted with the problem-solving steps is important. Thanks.

Cheers,
Wen Shih