Question

упростите выражение б) и в)

Answer 1

б)
$\frac{2sina + sin2a}{2sina - sin2a} = \frac{2sina + 2sinacosa}{2sina - 2sinacosa } = \frac{2sina(1 + cosa)}{2sina(1 - cosa)} = \frac{1 + cosa}{1 - cosa}$
в)
$\frac{1 + cos2a}{sin2a} = \frac{ 1 + 2{cos}^{2} a - 1}{2sinacosa} = \frac{2 {cos}^{2} a}{2sinacosa} = \frac{cosa}{sina} = tga$