Question

Let g be the function given by g(x)=x^2*e^(kx) , where k is a constant. For what value of k does g have a critical point at x=2/3?

Answer 1

g `( x ) =
`2x * e^(kx) + k x^(2) *e^(kx) = \\ = xe^(kx)(2 + kx )`
2 + k x = 0
k x = -2
k = -2: x = - 2 : 2/3 = - 2 * 3/2
k = - 3
Answer: for k= - 3, the function g ( x ) have a critical point at x = 2/3.