Math problems(please expiain!)

1.Y is not a real no. as all powers of 1=1

2.5^U=1
=5^0
U=0

3.Z is not a real no. as no. powers of any no.=0

5.f(x)=dividend(Q(x))+R whereQ(x) is the quotient & R is remainder
if Q(x)=0,f(x) dividend(0)+R
f(x)=R

there we can find the remainder by finding te corresponding value of x for the quotient equal to 0