Question

Elo❤️

If 2 sin square theta + 3 sin theta = zero find the permissible values of cos theta.


Thenks

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Answer 1

2sin^2x + 3sinx = 0

So,

2sin^2x = - 3sinx

sinx = - 3/2 when x not equal to zero..... But sinx can not be less than - 1

So sinx = 0 is a possible solution for this equation

Which means x = 0, pi

So, cosx = 1 or - 1

Nishant Abhangi

JEE ADVANCED 2019, AIR 6