Oblicz a) (cos45° - cos30°) * (cos45° + cos30°) - powinno wyjść -0,25 b) (3sin45° + tg60°) * (3sin45° - tg60°) - powinno wyjść 1,5 c) (sin60° + cos30°)² - (sin30° + cos60°)² - powinno wyjsc 2

a) [latex](frac{sqrt{2}}{2}-frac{sqrt{3}}{2})*(frac{sqrt{2}}{2}-frac{sqrt{3}}{2})=[/latex] [latex]=frac{2}{4}-frac{3}{4}=-frac{1}{4}=-0,25[/latex] b) [latex](3 cdot frac{sqrt{2}}{2}+sqrt{3})*(3 cdot frac{sqrt{2}}{2}-sqrt{3})=[/latex] [latex]=(frac{3sqrt{2}}{2})^2-(sqrt{3})^2=frac{18}{4}-3=4frac{1}{2}-3=1,5[/latex] c) [latex](frac{sqrt{3}}{2}+frac{sqrt{3}}{2})^2-(frac{1}{2}+frac{1}{2})^2=[/latex] [latex]=(frac{2sqrt{3}}{2})^2-1^2=(sqrt{3})^2-1^2=3-1=2[/latex]