How do you solve $sin2xcosx+sinx=0$ in the interval [0,360]?

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Answer 1 · 2016-10-07T20:45:10

$:. S={0,pi,2pi}$

$sin2xcosx+sinx=0$

$2 sinxcosxcosx+sinx=0$

$sinx(2cos^2x+1)=0$

$sinx =0 or 2cos^2x+1=0$

$x=sin^-1 0$ or $2cos^2x=-1->$ Not possible since we cannot take a square root of a negative number.

$x=sin^-1 0 = 0,pi,2pi$

$:. S={0,pi,2pi}$

How do you solve sin2xcosx+sinx=0sin2xcosx+sinx=0 in the interval [0,360]?