Question

1 ) Find the magnitude of angle A, if: (i) 2 sin A cos A - cos ssA - 2sin A + 1 = 0 (ii) tan A - 2 cos A anA + 2cos A - 1 = 0 (iii) 2cos^2 A - 3co A + 1 = 0 (iv) 2 tan 3A cos 3A - tan n 3A+1=2 cos 3A​

Answer 1

Step-by-step explanation:

i) 2tan3Acos3A−tan3A+1=2cos3A

2tan3Acos3A−tan3A−2cos3A+1=0

tan3A(2cos3A−1)−1(2cos3A−1)=0

(tan3A−1)(2cos3A−1)=0

Either tan3A−1=0 or 2cos3A−1=0

tan3A=1 or cos3A= 21

tan3A=tan45 or cos3A=cos60

3A=45 or 3A=60

A=15°

or A=20°

Thus, A=15° or20°