Question 1194315: If tan A = ¾ and cos B = 12/13, find
a. Tan (A - B)
b. c. tan ( B - A )
c. Sin ( A + B)
d. cos 2A Found 2 solutions by Alan3354, MathTherapy:Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website! If tan A = ¾ and cos B = 12/13, find
a. Tan (A - B)
b. c. tan ( B - A )
c. Sin ( A + B)
d. cos 2A
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tan(A) = 3/4
tan = y/x
r = sqrt(x^2 + y^2) = 5
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sin = y/r
cos = x/r
cot = 1/tan
sec = 1/cos
csc = 1/sin
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cos(B) = 12/13 = x/r ---> y = 5
sin = y/r
cos = x/r
tan = y/x
cot = 1/tan
sec = 1/cos
csc = 1/sin
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a. Tan (A - B)
b. c. tan ( B - A )
c. Sin ( A + B)
d. cos 2A
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Look up formulas at Wikipedia "Half angle formulas"
---- Email via the TY note for help or to check your work. Answer by MathTherapy(10552) (Show Source): You can put this solution on YOUR website! If tan A = ¾ and cos B = 12/13, find
a. Tan (A - B)
b. c. tan ( B - A )
c. Sin ( A + B)
d. cos 2A
This is a 3-4-5 Pythag. Triple, This is a 5-12-13 Pythag. Triple,
so hypotenuse = H = r = 5 so opposite = O = y = 5
Therefore, Therefore, a.
Make the necessary substitutions and you should have the answer.
b.
Make the necessary substitutions and you should have the answer,
or
Simply NEGATE a.
c. sin (A + B) = sin (A) cos (B) + cos (A) sin (B)
Make the necessary substitutions and you should have the answer.
d.
Make the necessary substitutions and you should have the answer.