Answer:
The answer is root 6 + root 2/4
Explanation:
Cos (15)
Rewrite the expression
write (15 degrees) as a difference
cos ( 45 degrees - 30 degrees)
cos ( 45 degrees - 30 degrees)
Expand the expression
Use cos ( t - s ) = cos (t) cos (s) + sin (t) sin (s)
to expand the expression
cos (45 degrees) cos ( 30 degrees) + sin ( 45 degrees ) sin ( 30 degrees)
cos (45 degrees) cos ( 30 degrees) + sin ( 45 degrees ) sin ( 30 degrees)
calculate the expression
use the trigonometric values table or unit circle to calculate the expression
root 2/root 2 × cos (30 degrees) + sin (45 degrees) sin (30 degrees)
root 2/root 2 × root 3/root 2 + sin (45 degrees) sin (30 degrees)
root 2/ root 2 × root 3/root 2 + root 2/root 2 × sin (30 degrees)
root 2/root2 × root 3/root 2 + root 2/root 2 × 1/2
root 2/root2 × root 3/root 2 + root 2/root 2 × 1/2
Multiply
root 2/root 2 × root 3/root 2 only
Multiply by the fractions
root 6/ root 4 + root 2/ root 2 × 1/2
Multiply root 2/ root 2 × 1/2 only
6 root / root 4 + root 2/ root 4
write all numerators above the denominator
root 6 + root 2 / 4