Question

simplify (xy+yz)²--(xy-yz)²

Answer 1

(xy)²+(yz)²+2xy²z-((xy)²+(yz)²-2xy²z)
=(xy)²+(yz)²+2xy²z-(xy)²-(yz)^2+2xy²z
=4xy²z

Answer 2

(xy+yz)² - (xy-yz)²
x²y² + y²z² +2xy²z - (x²y² +y²z² -2xy²z)
x²y² -x²y² +y²z² - y²z² +2xy²z +2xy²z
4xy²z