Question

корень(18)-корень(72)*sin17p/8=

Answer 1

$sqrt{18}-sqrt{72}*sin^2(frac{17pi}8)=sqrt{18}-sqrt{18*4}*sin^2(frac{17pi}8-2pi)=$

$=sqrt{18}(1-2*sin^2(frac{17pi}8-frac{16pi}8))=sqrt{18}(1-2*sin^2(frac{pi}8))=$

$sqrt{18}*cos(frac{pi}4)=sqrt{18}*frac{sqrt2}2=frac{6}2=3$