Find a vector-parametric equation r 1(t)=⟨x(t),y(t),z(t)⟩r→1(t)=⟨x(t),y (t),z(t)⟩ for the shadow of the circular cylinder x2+z2=9x2+z2=9 in the xzxz-plane.

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.