SOLUTION: Find the value of tan (a+b) if sin a = -5/13, cos b = 4/5
270 degrees < a < 360 degrees
270 degrees < b <360 degrees
Thank you so much!
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-> SOLUTION: Find the value of tan (a+b) if sin a = -5/13, cos b = 4/5
270 degrees < a < 360 degrees
270 degrees < b <360 degrees
Thank you so much!
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Question 589614: Find the value of tan (a+b) if sin a = -5/13, cos b = 4/5
270 degrees < a < 360 degrees
270 degrees < b <360 degrees
Thank you so much! Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! Find the value of tan (a+b) if sin a = -5/13, cos b = 4/5
270 degrees < a < 360 degrees (quadrant IV)
270 degrees < b <360 degrees (quadrant IV)
**
use tan addition formula:
tan(a+b)=(tan a+tan b)/1-tan a*tan b
if sin a=-5/13
tan a=-5/12
if cos b=4/5
tan b=-3/4
..
tan(a+b)=(-5/12-3/4)/1-5/12*3/4
tan(a+b)=(-14/12/1-15/48
tan(a+b)=(-14/12)/(33/48)≈-1.7
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