1) 2cos (-0.5x + π/4) = -2
cos (-0.5x + π/4) = -1
cos (0.5x - π/4) = -1
0.5x - π/4 = π + 2πn
0.5x = π + π/4 + 2πn
0.5x = 5π/4 + 2πn
x = 10π/4 +4πn
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2)2sin (π/3 - x/4) = √3
sin (π/3 - x/4) = 0.5√3
sin (-π/3 + x/4) = -0.5√3
a) (-π/3 + x/4) = -π/3 + 2πn b) (-π/3 + x/4) = -2π/3 + 2πn
x/4 = 2πn x/4 = -π/3 + 2πn
x1 = 8πn n∈Z x2 = -4π/3 + 8πn n∈Z
уменьшаемое - вычитаемое = разность;
уменьшаемое = вычитаемое + разность;
2a²-4a+7a²-9a=9a²-13a;
3х^2+12х-х-4=0
3х2+11х-4=0
Д=169
х1=1/3
х2=-4
1) ...=3х-1+2х+6=х+7=42; х=42-7=35
2) ...=7х+3-5х-2=2х+1=42; 2х=42-1=41; х=41:2=20,5
3) ...=4-3х+2+х=6-2х=42; 2х=6-42= -36; х= -36:2= -18
4) ...=5х-6-2х-3=3х-9=42; 3х=42+9=51; х=51:3=17