Does x^4 * e^x have a horizontal asymptote?
Take the derivative to see if slope is zero.
dU/dx = x^4 * e^x
= 4x^3 * e^x + x^4 * e^x
So, what happens as x approaches neg large ?
Take the derivative to see if slope is zero.
dU/dx = x^4 * e^x
= 4x^3 * e^x + x^4 * e^x
So, what happens as x approaches neg large ?