simlify the following to the lowest terms: (a) [x^2-y^2]/[x^2+y^2] (b) [3a^2+6ab-a-2b]/[9a^2-6a+1] (c) [x^4-y^4]/[x^3-y^3] (d) [36x^3y^4z]/[64x^5y^2z^3]

Question

simlify  the following to the lowest terms: (a) [x^2-y^2]/[x^2+y^2]     (b) [3a^2+6ab-a-2b]/[9a^2-6a+1]   (c) [x^4-y^4]/[x^3-y^3] (d) [36x^3y^4z]/[64x^5y^2z^3]