\
The values are and
.
The angle is lies in first quadrant.
The value of cosine function is .
The angle is lies in fourth quadrant.
The point is lies on the curve of radius
.
Thus,
\The value of sine function is .
\
(a)
\The expression is
Sum formula for the sine function: .
Substitute and
in above equation.
Thus, .
\
(b)
\The expression is .
Sum formula for the cosine function: .
Substitute and
in above equation.
Thus,
\.
\
(c)
\The expression is .
Subtraction formula for the sine function:
Substitute and
in above equation.
Thus, .
\
(d)
\The expression is .
Subtraction formula for the cosine function:
From (c), .
.
(a). .
(b). .
(c). .
(d). .