Hello guys, I'm still learning how to do more advanced techniques with the TI-Nspire. Can you help me figure this one problem that I'm having out?

I'm using the right difference quotient. f(x+h)-f(x)/h

For (fx) = x^2-4x+7, find f(x+h)-f(x)/h

msec =

TI Nspire Function

rightdiff(x,h):= f(x+h)-f(x)/h

when I plugin rightdiff(x^2-4x+7, h) The answer is not coming out reduced as 2x+h-4.