## Algebra and Trigonometry 10th Edition

By squaring the binomial $u+v$: $(u+v)^2=(u+v)(u+v)=uu+uv+vu+vv=u^2+2uv+v^2$ By squaring the binomial $u-v$: $(u-v)^2=(u-v)(u-v)=uu-uv-vu+(-v)(-v)=u^2-2uv+v^2$