In quadrant I
cos θ = √2 / 2
for
θ = π / 4 rad (45°)
sin θ = sin π / 4
sin θ = √2 / 2
tan θ = sin θ / cos θ = ( √2 / 2 ) / ( √2 / 2 ) = 1
Find cos0 if sin0 =sqrt 2/2 and 0 terminates in quadrant I
3 answers
sin^2θ + cos^2θ = 1
1/2 + cos^2θ = 1
...
1/2 + cos^2θ = 1
...
sin A = y/r = sqrt2/2
x^2 + y^2 = r^2
x^2 + 2 = 4
X = sqrt2.
Cos A = x/r = sqrt2/2.
x^2 + y^2 = r^2
x^2 + 2 = 4
X = sqrt2.
Cos A = x/r = sqrt2/2.