4 cos^2 x =2+2sinx .. wht is the solution of the equation in the interval [0,2pie) ? i got no solution but i m nt sure
\[ 4 \cos^2 (x) =2+2\sin (x)\\ 4( 1- \sin^2(x))= 2+2\sin (x)\\ 4 -4\sin^2(x)= 2+2\sin (x)=0\\ -4 +4\sin^2(x)+ 2+2\sin (x)=0\\ 4\sin^2(x)+2\sin (x)-2=0\\ 2\sin^2(x)+\sin (x)-1=0\\ \] Can you finish it now?
Use the quadratic formula to find \[ \sin(x) = -1\\ \sin(x) = \frac 1 2 \]
\[ x= \frac {3 \pi}2\\ x= \frac \pi 6\\ x= \frac {5\pi}6 \]
thanks a lot
hey eliasaab if u could just check my answers for this question it would be a great help
the sign of the tan should be negative the sign of the sec should be positive
You can practice trig problems on my site http://www.math.missouri.edu/escgi/mucgi-bin/munew.cgi?variable=trig
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