Solve 3sinx 4cosx 2 Exact solutions are not possible for t
Solve 3sinx + 4cosx = 2. Exact solutions are not possible for this problem. To complete the solution, you will need to use a calculator. Use radian mode.
Solution
3sin x + 4cos x = 2
3 sin x = 2 - 4 cos x
(3sin x )^2 = ( 2- 4 cos x )^2
9 sin^2 x - ( 2 - 4 cos x )^2 = 0
sin^2 x = ( 1- cos^2 x )
on simplifying we get
5 + 16cos x - 25cos^2 x = 0
cos x = 1/25 ( 8 - 3 sqrt 21)
cos x = 1/25 ( 8 + 3 sqrt 21)
for, cos x = 1/25 ( 8 - 3 sqrt 21)
x = 2pi*n - arccos(1/25 ( 8 - 3 sqrt 21) ) , 2pi*n + arccos(1/25 ( 8 - 3 sqrt 21) )
cos x = 1/25 ( 8 + 3 sqrt 21)
x = 2pi*n - arccos(1/25 ( 8 + 3 sqrt 21) ) , 2pi*n + arccos(1/25 ( 8 + 3 sqrt 21) )
