<span>3x+2x+-7x=-4+3+5
-2х = 4
2х = -4
х = -2</span>
-4sin^2альфа +5-4cos^2альфа=-4(1-cos^2альфа)+5-4cos^2альфа=-4+4cos^2альфа+5-4cos^2альфа=1
<span>(x²+4x+1)(x²+4x+5) = -4</span>
<span>(x²+4x+1)(x²+4x+1 + 4) = -4</span>
<span>x²+4x+1 = t
t ( t + 4 ) + 4 = 0
t² + 4t + 4 = 0
t1 = t2 = -2
</span><span>x²+4x+1 = -2
</span><span>x²+4x+3 =</span> 0
х1= -1 х 2= -3
Ответ; -1: -3.