Q. If cosA=5328 and tanB=125 and angles A and B are in Quadrant I, find the value of tan(A+B).Answer:
Find tanA: Use the identity for the tangent of a sum of two angles: tan(A+B)=1−tanA⋅tanBtanA+tanB. First, we need to find tanA using the given cosA=5328. Since cosA=hypotenuseadjacent, we can find the opposite side using the Pythagorean theorem: opposite2=hypotenuse2−adjacent2.
Calculate opposite side: Calculate the opposite side for angle A: opposite2=532−282.opposite2=2809−784.opposite2=2025.opposite=2025.opposite=45.
Find tanB: Now we can find tanA: tanA=adjacentopposite.tanA=2845.
Apply tan(A+B) identity: We already have tanB given as 125.Now we can use the identity for tan(A+B): tan(A+B)=1−tanA⋅tanBtanA+tanB.tan(A+B)=1−(2845⋅125)2845+125.
Add fractions: Find a common denominator for adding the fractions2845 and 125. The common denominator is 84. Convert the fractions: (2845)×(33)=84135 and (125)×(77)=8435. Now add the fractions: 84135+8435=84170.
Simplify fraction: Simplify the fraction84170 by dividing both numerator and denominator by 2.84170=4285.
Calculate denominator: Now calculate the denominator of the tan(A+B) formula: 1−(2845×125). First, multiply the fractions: (2845)×(125)=336225. Simplify the fraction 336225 by dividing both numerator and denominator by 3. 336225=11275.
Subtract fraction from 1: Now subtract the fraction from 1: 1−11275. Convert 1 to a fraction with the same denominator: 112112−11275=11237.
Calculate tan(A+B) formula: Now we have both the numerator and the denominator for the tan(A+B) formula.tan(A+B)=4285/11237.To divide by a fraction, multiply by its reciprocal: 4285×37112.
Multiply fractions: Multiply the fractions: (85×112)/(42×37).85×112=9520 and 42×37=1554.tan(A+B)=15549520.
Simplify fraction: Simplify the fraction 15549520 by finding the greatest common divisor (GCD) and dividing both numerator and denominator by it.The GCD of 9520 and 1554 is 2.29520=4760 and 21554=777.tan(A+B)=7774760.
Simplify further: Simplify the fraction 7774760 further if possible.The GCD of 4760 and 777 is 1, so the fraction is already in its simplest form.tan(A+B)=7774760.
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