Question

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Question :
1. Find the gradient of the tangent to the curve y = 2x²+5x-3 at the point where x = 1.

2. Find from first principle, the derivative of 3/x with respect to x​

Answer 1

dy/dx

= d/dx [2x² + 5x - 3]

= 4x + 5.

Hence at x = 1, dy/dx = 4(1) + 5 = 9.

The slope of the tangent is 9.

d/dx (3/x)

= d/dx (3x^-1)

= 3 * d/dx (x^-1)

= 3 * [-1 * x^(-2)]

= -3/x².