5х-2(х-3)=6х
5х-2х+6=6х
3х-6х=-6
-3х=-6
х=2
6х -(2х+5)=2(3х-6)
6х-2х-5=6х-12
-2х=-7
х=3,5
х(х+5)=(х+3)
х^2+5х=х^2+6х+9
-х=9
х=-9
Cos(5x/2-1)=-2/3
5x/2-1=+-(π-arccos2/3)+2πn
5x/2=1+-(π-arccos2/3)+2πn
x=2/5+-2/5(π-arccos2/3)+4πn/5,n∈z
b2/3:b1/2=b4/6:b3/6=b4/6*b6/3=b4/3
(cos pi/4*cos 2x + sin pi/4*sin 2x) - √2sinx = √2(sin2x + 1)
2(√2/2*cos 2x + √2/2 *sin2x) - √2sinx = √2(sin 2x +1);
2*√2/2 (cos 2x + sin 2x) - √2sinx = √2(sin 2x +1);
cos2x + sin 2x -sinx = sin 2x +1;
1 - 2sin^2 x - sinx = 1;
-sinx(2sinx+1)=0;
1) sinx = 0; x1=pin, n---Z.
2) 2sinx+1=0; sinx= -1/2; x2=(-1)^n(-pi/6)+pin, n---Z.
1 фото: В
2 фото: Г
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