Trig Equation! - Need Help! (1 Viewer)

[melissa92]

Solve the equation:

2sin^2 x = sin2x

for 0<x<360.

thx...I tried to many ways of doing it, but it's complicated.

 

[Timothy.Siu]

Solve the equation:

2sin^2 x = sin2x

for 0<x<360.

thx...I tried to many ways of doing it, but it's complicated.

2sin^2 x=2sin x cos x
2sin^x-2sin x cos x=0
2sin x(sin x-cos x)=0
2sin x(sqrt2sin(x-45)=0
x=0 or 180 or 360 or 45 or 225

 

[melissa92]

WOW..thank you ^_^..

i got up to the 2sinx(sinx - cosx) = 0, and that was it..thank you so much ^_^

 

[Timothy.Siu]

WOW..thank you ^_^..

i got up to the 2sinx(sinx - cosx) = 0, and that was it..thank you so much ^_^

np, u've learnt transformations right? i hope so,

 

[melissa92]

yup..^_^..but this question was hard, the rest was fine ^_^..

thank you once again.