Posted by Kayla on Tuesday, March 22, 2011 at 10:03pm.
Have you come across the identity
cos(A-B) = cosAcoB + sinAsinB ?
your question fits that pattern perfectly.
Let me know what you get.
ok I made a mistake in the formula. it's cos(20 degrees)cos(70 degrees)- sin(20 degrees) sin(70 degrees).
so it's a subraction equation not an addition.
and of course there is the matching formula for
cos(A+B) = cosAcosB - sinAsinB
So what do you think?
so it would be cos(20+70)?
cos(20 degrees+70 degrees) i mean
yes, but what is cos(20° + 70°) ??
= cos 90°
cos(20 degrees)cos(70 degrees)- sin(20 degrees) sin(70 degrees)
Yeah I got the exact value I just needed it in trigonometric function of one number which would be the degrees of cos.
HELP ME !
sin50 cos 20 - cos 50 sin 20
^find exact value
Pls tell me how to find out sin70.Pls
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