Question

若(Y-5)的零次无意义,且3x+2y=1,则Y的X次方=?

Answer 1

y-5=0 y=5

3x+2y=1

x=-3

y^x=5^(-3)=1/125

a+1/a=6

(a+1/a)^2=36

a^2+1/a^2+2=36

a^2+1/a^2=34

(a-1/a)^2=a^2+1/a^2-2=34-2=32

10^a=20

a=lg(2*10)=lg2+1

10^b=1/5

b=lg(1/5)=lg(2/10)=lg2-1

a-b=lg2+1-(lg2-1)=2