Question

z3⋅z3:z5
------------- ( цифры- это степени )
z9⋅z8:z17

Answer 1

$frac{z^3z^3:z^5}{z^9z^8:z^{17}}} = frac{z^{3+3-5}}{z^{9+8-17}} =z$

Answer 2

z^3*z^3:z^5=z^6 : z^5=z
z^9 * z^8 : z^17=z^17 " z^17 =1
z : 1 = z