Find 2 given that =
−4/5 and < < 3/2
we know that
sin(2x) = 2 sin(x) cos(x)
so
step 1
Find the value of cos(x)
Remember that
[tex]\sin ^2(x)+\cos ^2(x)=1^{}[/tex]we have
sin(x)=-4/5
The angle x lies on III quadrant
that means
cos(x) is negative
substitute the value of sin(x)
[tex]\begin{gathered} (-\frac{4}{5})^2+\cos ^2(x)=1^{} \\ \\ \frac{16}{25}+\cos ^2(x)=1^{} \\ \\ \cos ^2(x)=1-\frac{16}{25} \\ \cos ^2(x)=\frac{9}{25} \\ \cos (x)=-\frac{3}{5} \end{gathered}[/tex]step 2
Find the value of sin(2x)
sin(2x) = 2 sin(x) cos(x)
we have
sin(x)=-4/5
cos(x)=-3/5
substitute
sin(2x)=2(-4/5)(-3/5)
