Question

d) sin 60° x cos 45° - 2xsin 45° x cos 60° + sin 45=?

e) sin 60° x ctg 60° + cos 45° x tg 45° - sin 30° =?Va rog ajutati ma​

Answer 1

Răspuns:

poza

Explicație pas cu pas:

poza

Answer 2

$\it d)\ sin60^o\cdot cos45^o-2sin45^ocos60^o+sin45^o =\dfrac{\sqrt3}{2}\cdot\dfrac{\sqrt2}{2}-2\cdot\dfrac{\sqrt2}{2}\cdot\dfrac{1}{2}+\dfrac{\sqrt2}{2}=\\ \\ \\ = \dfrac{\sqrt6}{4}-\dfrac{\sqrt2}{2}+\dfrac{\sqrt2}{2} =\dfrac{\sqrt6}{4}$