SOLUTION: Please help me! Thank you so much! Write the expression as the sine, cosine, or tangent of an angle: sin 49° cos 11° - cos 49° sin 11°

Algebra ->  Trigonometry-basics -> SOLUTION: Please help me! Thank you so much! Write the expression as the sine, cosine, or tangent of an angle: sin 49° cos 11° - cos 49° sin 11°      Log On


   

Question 869639: Please help me! Thank you so much! Write the expression as the sine, cosine, or tangent of an angle: sin 49° cos 11° - cos 49° sin 11°
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
I would use the trigonometric identity
sin%28A%2BB%29=sin%28A%29%2Acos%28B%29%2Bcos%28A%29%2Asin%28B%29
and the fact that sin%28-B%29=-sin%28B%29 .



NOTE:
Someone may say to use
sin%28A-B%29=sin%28A%29%2Acos%28B%29-cos%28A%29%2Asin%28B%29 ,
but that means one more formula.
I do not believe in memorizing, so I just rediscover the formulas with a + sign each time I need one of them.