Use the difference formulas for and :Originally Posted by xanith_47
and:
So if :
Hence:
RonL
Im not a very good mathematician, and im only in grade 10..and need some help
Question is: Show
sin(180-sinB)
____________ = -tanB
cos(180-B)
Sorry if this question is really easy, i must really suck.
Ive tried doing it:
sinB
____ = tan B
cosB
.: sin B- sinx
___________ = -tanx
cos B- cosx
Is this method right, and in an exam will i get full marks for it?
Another question:
Simplify cos(90-b)
_________
sin(180-b)
I havent the slightest idea what to do.
I understand that cosx over sinx= 1/2 x tanx..but the values of cos and sin are different in this question... so is it implying that the answer is:
cos90- cos b
_____________ = 1/4 x tan (since cos over sin is 1/2tan, this is half)
sin 180- sin b
And i need to solve for b....
Thanks in advance.