5x² - ( 5x² + 19x - 4) = 5x² - 5x² - 19x + 4 = - 19x+ 4
При x=0,1:
- 19x + 4 = - 19 × (0,1) + 4 = - 1,9 + 4 = 2,1
Корни убираются
1. х+2=3х+4
х-3х=4-2
-2х=2
х=-2
2. 4-2х=х-2
-2х-х=-2-4
-3х=-6
х=2
<span>а) cos x + sin y = cosx+cos(p/2-y)=2cos((x-y)/2+p/4)cos((x+y)/2-p/4)
б) cos x - sin x= cosx+cos(p/2+x)=2cos(x+p/4)cos(p/4)=</span>√2cos(x+p/4)
<span>в) sin 2x - cos x=cos(p/2-2x)-cosx=-2sin(p/4-x/2)sin(p/4-3x/2)</span>
-5×2×(-3)^3+8×2^2×(-3)=-10×(-27)+32×(-3)=270-96=174