Question

which expression is in simplified form for the given expression and states the correct variable restriction u+3/u^2-9

Answer 1

Simplifying the expression given we shall have:
(u+3)/(u²-9)
factorizing (u²-9)=(u-3)(u+3)
thus plugging the substitute in the expression we shall have:
=(u+3)[(u-3)(u+3])
=1/(u-3)
Hence the answer is 1/(u-3)
u can take any values except 3.