Question

sin2x+cos2x if tan=2 and cos> 0

Answer 1

solve for cos with tan(squared) + 1 = sec(squared)

Answer 2

4 + 1 = sec(squared)
squareroot(5) = sec
sec = 1/ cos
1/ squareroot(5) = cos

Answer 3

now solve for sin with 1 + cot(squared) = csc(squared)

Answer 4

1 + (1/4) = csc(squared)
5/4 = cc(squared)
csc = squareroot(5)/2
csc = 1/ sin
2/ squareroot(5) = sin

Answer 5

so sin 2x = 2 * sinx * cosx
and
cos 2x = cosx(squared) - sinx(squared)

Answer 6

plug it in
\[2 \times sin(2\div \sqrt{5}) \times cos(1\div \sqrt{5}) = \sin 2x\]
\[\cos(1\div \sqrt{5})^{2} - \sin(2\div \sqrt{5}) = \cos 2x\]

Answer 7

sin2x = 0.8
cos2x = -0.6
sin2x + cos2x
0.8 - 0.6 = 0.2