SOLUTION: sin 50 degrees equals 2 sin 25 degrees.... true or false? Also an explanation please?

Click here to see ALL problems on Trigonometry-basics

Question 212337This question is from textbook
: sin 50 degrees equals 2 sin 25 degrees.... true or false? Also an explanation please? This question is from textbook

Found 3 solutions by stanbon, rapaljer, Alan3354:
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website!
sin 50 degrees equals 2 sin 25 degrees.... true or false?
---------------------
Ans: False
---------------------
Why?: sin(50) = sin(2*25) not 2*sin(25)
-----------------------------------
Cheers,
Stan H.

Answer by rapaljer(4671)   (Show Source):
You can put this solution on YOUR website!
False!! It is NOT true that sin(AB) = A*sin(B)

R^2

Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website!
Sin(25) = 0.422618261
2sin(25) = 0.845236523
-------------
sin(50) = 0.766044443
---------------------
Or,
sin(2*25) = 2sin(25)cos(25)
then, is 2sin(25)cos(25) = 2sin(25)?
2sin(25)cos(25) = 2sin(25)?
cos(25) = 1?
No, cos(0) = 1