Question

Найдите значение выражения 14sin 135°*cos45°

Answer 1

14sin(90°+45°)*cos45°=14sin(90°+45°)*cos45°=14cos45°*cos45°=

14cos²45°=14(1/2)=7;

Answer 2

14Sin135° * Cos45° = 14Sin(90° + 45°) * Cos45° = 14 * (  Cos45°) * Cos45° =

=  14 Cos² 45° = $14*(frac{sqrt{2}} {2}) ^{2}=14* frac{1}{2}=7$