-8х=56 х=-7 х=-7 х=-7
3у-4х=46 3у-28=46 3у=18 у = 6
Е)
х=6+у
4(6+у)-у-3=0
24+4у-у-3=0
3у+21=0
3у=-21
у=-7
х=6-7=-1
(-1;-7)
Y=2x+4; k=2
y=-2x+4; k=-2
y=2x-4 k=2
f(x)=2x+4 ║ f(x)=2x-4
f(x)=-2+4 ∩ f(x)=2x+4
f(x)=-2+4 ∩ f(x)=2x-4
Графики во вложении
Cosx=-1/2 x=+-(π-π/3)+2πk =+-2π/3+2πk k∈Z
cosx=-1 x=π+2πk k∈Z
2cosx=1 cosx=1/2 x=+-π/3+2πk k∈Z
cosx=1/√2=√2/2 x=+-π/4+2πk k∈Z