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Litt vrien likning

x E [0, 180]

sin x + 2 cos x = 1

Trenger hjelp, Takk

[tex]\sin x + 2\cos x = 1[/tex]

[tex]2\cos x = 1-\sin x[/tex]

[tex](2\cos x)^2=(1-\sin x)^2[/tex]

[tex]4\cos^2x=1-2\sin x + sin^2 x[/tex]

Husk at [tex]\cos^2x+\sin^2x=1[/tex] da er [tex]4\cos^2x=4(1-\sin^2x)[/tex]

Resten tar du selv?