# Prove that if 4sin e+4cos^2 e-5=0 then sin e = 1/2

Trigonometry equalities, inequalities and expressions - sin, cos, tan, cot

### Prove that if 4sin e+4cos^2 e-5=0 then sin e = 1/2

If 4sin ө+4cos^2 ө-5=0 then prove that
sin ө=1/2
nisarg

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### Re: Prove that if 4sin ө+4cos^2 ө-5=0 then sin e = 1/2

$$cos^2e = 1-sin^2$$

so
$$4sin(e) + 4(1-sin^2(e)) - 5 = 0$$

this is a quadratic equation that you need to find the roots of sin e
The equation should have 2 roots one of them to be 1/2
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