If 1 + Tana / 1-taba = 3 + 2 √ 2, then sin2a How to simplify Cosa √ 2siina

(1+tanA)/(1-tanA)=(cosA+sinA)/(cosA-sinA)=3+2√2
It is reduced to cosa = √ 2sina
Because cosa2 + sina2 = 1
So sina2 = 1 / 3
sin2A=2sinAcosA=2√2/3

It is known that sin = 3 / 5, sin2a

From sin2a = 2sinacosa < 0,
Where Sina = 3 / 5, ﹤ cosa < 0
cosA=-√（1-9/25）=-4/5.
∴tanA/2=（1-cosA）/sinA
=3.

In the triangle ABC, Tana = radical, sin2a =

Tana = root sign, angle a = 60 degrees
Sin2 α = 2Sin α cos α = radical 3 / 2

Tana = 2, find 1 / (sin2a)

tanA=2,
sinA/cosA=2
sinA=2cosA
sin²A+cos²A=1
5cos²A=1
cos²A=1/5
1/(sin2A)=1/(2sinAcosA)
=1/(4cos²A）
=1/(4/5)
=5/4

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