Question 825051
How to do it: If theta and beta belong to Q1, and cot theta = 12/13,
sin beta = √ 2/2, tan (theta + beta) is equal to:
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letx=theta
lety=beta
Identity: tan(x+y)={{{(tan(x)+tan(y))/(1-tan(x)tan(y))}}}
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cotx=12/13 (given)
tanx=13/12
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siny=√2/2 (working with a 45˚ right triangle)
tany=1
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tan(x+y)={{{(13/12+1)/(1-13/12*1)=(25/12)/(1/12)=25}}}
ans: c)25