(√320-3∛24)(√45- 2∛81) (sin∝-cos∝)2+ (sin∝+cos∝)2 у=cos(0,5x- π/2) (lg2+lg3)/(lg3,6+1)...

Question

(√320-3∛24)(√45- 2∛81)
(sin∝-cos∝)2+ (sin∝+cos∝)2
у=cos(0,5x- π/2)
(lg2+lg3)/(lg3,6+1)
cos^(2)x-4cosx+3=0

Answer 1

1
(8√5-3*2∛3)(3√5-2*3∛3)=(8√5-6∛3)(3√5-6∛3)=120-48√5∛3-18√5∛3+36∛9=
=120-66√5∛3+36∛9
2
sin²a-2sinacosa+cos²a+sin²a+2sinacosa+cos²a=2(sin²a+cos²a)=2
3
y=cos(0,5x-π/2)=cos(π/2-0,5x)=sin0,5x
4
(lg2+lg3)/(lg3,6+lg10)=lg6/lg36=log(36)6=1/2
5
cosx=a
a²-4a+3=0
a1+a2=4 U a1*a2=3
a1=1⇒cosx=1⇒x=2πn,n∈z
a2=3⇒cosx=3>1 нет решения