1) (с³-5cd-3d)+(c³+5d+8cd)= c³-5cd-3d+c³+5d+8cd= 2c³+2d+3cd
2) (-5y-4x⁴-2x²y)+(-5x²y-6y-5x⁴)= -5y-4x⁴-2x²y-5x²y-6y-5x⁴=-11y-9x⁴-7x²y
3) (-2m²+3n+6mn²)-(2mn²+3n+m²)= -2m²+3n+6mn²-2mn²-3n-m²=-3m²+4mn²

0 0

3 года назад

2cos^2x+cos3x+cos4x=1

ifreestyler

$2cos^{2} x + cos 3x + cos 4x = 1 \\ \frac{2(1 +cos 2x)}{2} + cos 3x + cos 4x = 1 \\ 1 + cos 2x + cos 4x + cos 3x -1 = 0 \\ cos 2x + cos 4x + cos 3 x = 0 \\ 2 cos \frac{2x - 4x}{2} cos \frac{2x + 4x}{2} + cos 3x = 0 \\ 2 cos x cos 3x + cos 3x = 0 \\$
$cos 3x (2cos x +1) = 0 \\ 1) cos 3x = 0 \\ cos t = 0 \\ t = \frac{ \pi }{2} + \pi k \\ 3x = \frac{ \pi }{2} + \pi k \\ x_{1} = \frac{ \pi }{6} + \frac{ \pi k}{3} \\ 2) 2 cosx + 1 = 0 \\ cosx = - \frac{1}{2} \\ x_{2} = +- \frac{2 \pi }{3} + 2\pi k$

0 0

3 года назад

Решите уравнение : 9х^2-1=(3x-2)^2

Serg113

9х²-1=9х²-12х+4

0 0

4 года назад