A curve has equation y=k/x. Given that the gradient of the curve is -3 when x=2. Find the value of constant k. ?

A curve has equation y=k/x. Given that the gradient of the curve is -3 when x=2. Find the value of constant k.

1 Answer
Jan 21, 2018

k=12

Explanation:

•color(white)(x)m_(color(red)"tangent")=dy/dx" at x = 2"

y=k/x=kx^-1

rArrdy/dx=-kx^-2=-k/x^2

-k/x^2=-3" when "x=2

rArr-k=-3xx4=-12rArrk=12