Given Find Given f x 7x2 5x 8 Find fx h fxhSolutionfx

Given

Find

Given f (x) - 7x^2 - 5x + 8 Find f(x + h) - f(x)/h

Solution

f(x) = -7x^2 -5x +8

Plug x= x+h ; f(x+h) = -7(x+h)^2 -5(x+h) +8

f(x) = -7x^2 -5x +8

{ f(x+h) -f(x) }/h = { -7(x+h)^2 -5(x+h) +8 - (-7x^2 -5x +8) }/h

=( -7x^2 -7h^2 - 14xh -5x -5h +8 + 7x^2 +5x - 8 )/h

= ( -7h^2 -14xh -5h)/h

= -7h -14x -5