Mathematics, 25.11.2020 04:20 sugandiwoodbine

HELP ASAP PLZ Given sinx = 2/3 and cos < 0 a) Use double identities to find the exact values of sin2x and cos2x

I got cos2x =1/9 and sin2x = $\frac{4\sqrt{5} }{9}$

I'm just confused on how to do b & c.

b) Use a Pythagorean Identity to verify the answers you found for sin2x and cos2x.

c) Use a Ratio Identity to find tan2x. Do not use the double angel identity for tangent.

Answers: 3

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HELP ASAP PLZ Given sinx = 2/3 and cos < 0 a) Use double identities to find the exact values of...