Q. If cosA=3735 and sinB=5328 and angles A and B are in Quadrant I, find the value of tan(A+B).Answer:
Find sinA and cosB: Use the given values to find sinA and cosB. Since cosA=3735, we can use the Pythagorean identity sin2A+cos2A=1 to find sinA. sin2A=1−cos2Asin2A=1−(3735)2sin2A=1−13691225cosB0cosB1cosB2cosB3
Find cosB using sinB: Similarly, find cosB using sinB=5328. cos2B=1−sin2B cos2B=1−(5328)2 cos2B=1−2809784 cos2B=28092809−2809784 cos2B=28092025 cosB=28092025 sinB0
Use angle sum identity for tangent: Use the angle sum identity for tangent to find tan(A+B).tan(A+B)=1−tanA⋅tanBtanA+tanBSince tanA=cosAsinA and tanB=cosBsinB, we can substitute the values we found.tanA=35/3712/37=3512tanB=45/5328/53=4528tan(A+B)=1−(3512⋅4528)3512+4528
Simplify expression for tan(A+B): Simplify the expression for tan(A+B).tan(A+B)=3512+4528 / 1−(3512⋅4528)To add the fractions, find a common denominator, which is 35⋅45.tan(A+B)=35⋅45−(12⋅28)(12⋅45)+(28⋅35)tan(A+B)=1575−336540+980tan(A+B)=12391520
Check for simplification: Check for any possible simplification of the fraction.The numerator and denominator of 12391520 do not have any common factors other than 1, so the fraction is already in its simplest form.
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