Simplify each expression and state any non-permissible values. ( 3 marks - show your work)

x/ x^2-3x-4 - 4/x+1

I assume

x/(x^2-3x-4) - 4/(x+1) ?????

x/[(x+1)(x-4)] - 4(x-4)/[(x+1)(x-4)]

-3x+4 /[(x+1)(x-4)]

blows up if x = -1 or x = 4