Question

A solutiob of thr equation cos 2 theta + sin 2 theta = -1

Answer 1

cos2x+sin2x=-1

Answer 2

multiply each side by 1/(sqrt2)

Answer 3

\[\frac{ 1 }{ \sqrt{2} }*\cos2x+\frac{ 1 }{ \sqrt{2} *\sin2x}=\frac{ -1 }{ \sqrt{2} }\]

Answer 4

\[\frac{ 1 }{ \sqrt{2} }=\cos45=\sin45\]

Answer 5

\[\sin45*\cos2x+\cos45*\sin2x=\sin(45+2x)=\frac{ -1 }{ \sqrt{2} }\]

Answer 6

\[\frac{ \pi }{ 4 }+2x=\sin^{-1}(\frac{ -1 }{ \sqrt{2} })=-\frac{ \pi }{ 4 }\]

Answer 7

2x==-pi/4-pi/4=-pi/2
x=-pi/4

Answer 8

it can have many solution this is just one