Question

Find sin2x and cos2x when tanx= sqrt 2. PLEASE HELP SOLVE

Answer 1

You mean sin^2(x) or sin(2x)?

Answer 2

sin2x so double angle formula.. not sure where to begin with tangent

Answer 3

Use pythagorus to find ? and go from there

Answer 4

ok that was wrong!

Answer 5

so you have
\[\sin(x)=\frac{\sqrt{2}}{\sqrt{3}}\] and
\[\cos(x)=\frac{1}{\sqrt{3}}\] use those to find
\(\sin(2x)\) and \(\cos(2x)\)

Answer 6

how did you find rad 3 as the hypotenuse?

Answer 7

they hypotenuse is
\[\sqrt{1^2+\sqrt{2}^2}=\sqrt{1+2}=\sqrt{3}\] by pythagoras

Answer 8

*the

Answer 9

okay with that?

Answer 10

yeah that clicks to me now! thank you so much

Answer 11

yw
it is good from there, right?
\[\sin(2x)=2\sin(x)\cos(x)=2\times \frac{1}{\sqrt3}\times \frac{\sqrt2}{\sqrt3}=\frac{2\sqrt2}{3}\] etc

Answer 12

got it from there!! thanks again