Question

Find (cosA+sinA)^2+(cos A-Sin a)^2

a) -2
b) 2
c) 1

Answer 1

Solution:

Solution:
(cos(a)+sin(a))^2+(cos(a)-sin(a))^2

=(cos(a)+sin(a))^2+(cos(a)-sin(a))^2

=(cos^2(a)+2cos(a)sin(a)+sin^2(a))+(cos(a)-sin(a))^2

=(1+2cos(a)sin(a))+(cos(a)-sin(a))^2

=1+2cos(a)sin(a)+(cos(a)-sin(a))^2

=1+2cos(a)sin(a)+(cos^2(a)-2cos(a)sin(a)+sin^2(a))

=1+2cos(a)sin(a)+(1-2cos(a)sin(a))

=2

The correct answer is b.

Hope it will help.

Answer 2

Step-by-step explanation:

If θ be an acute angle, the values of sin θ and cos θ lies between 0 and 1 (both inclusive). The sine of the standard angles 0°, 30°, 45°, 60° ...

ur answer is -2