Question

cos671/2°= solve it​

Answer 1

Answer:

$\cos(335.5) \\ 0.9099612$

hope this will help you

Answer 2

ANSWER=

√2-1/2√2

STEP BY STEP EXPLANTION

cosθ=±√ 1+cos2θ/2  

cos671/2°

=cos135°/2

=1+cos135°/2

=1+cos(90°+45°)/2

=√1−sin45°/2

=√1−1/√2/2