SOLUTION: Find the values of the trigonometric functions of t from the given information.
csc(t) = 3, cos(t) < 0
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-> SOLUTION: Find the values of the trigonometric functions of t from the given information.
csc(t) = 3, cos(t) < 0
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You can put this solution on YOUR website! Find the values of the trigonometric functions of t from the given information.
csc(t) = 3, cos(t) < 0
3 is a positive number. The cosecant is positive in QI and QII.
The cosine is negative in QII and QIII. Therefore t must be in
QII.
The cosecant is r/y or the hypotenuse over the opposite. Therefore we
take 3 as the fraction 3/1 and consider the r=3 as the hypotenuse,
which is ALWAYS taken positive, and y=1 as the opposite. We use the Pythagorean theorem:
(hypotenuse)² = (adjacent)² + (opposite)²
r² = x² + y²
3² = x² + 1²
9 = x² + 1
8 = x²
±√8 = x
±2√2 = x
In QII the adjacent = x is negative, so we take the negative sign
x = -2√2.
adjacent = x = -2√2, opposite = y = 1, hypotenuse = r = 3
sin(t) = opposite/hypotenuse = y/r = 1/3
cos(t) = adjacent/hypotenuse = x/r = -2√2/3
tan(t) = opposite/adjacent = y/x = 1/(-2√2) = [1/(-2√2)][√2/√2] =
= (√2)/(-2∙2) = -√2/4
sec(t) = hypotenuse/adjacent = r/x = 3/[-2√2] = [3/(-2√2)][√2/√2] =
= (3√2)/(-2∙2) = -3√2/4
csc(t) = hypotenuse/opposite = r/y = 3/1 = 3 (given!)
cot(t) = adjacent/opposite = x/y = -2√2/1 = -2√2
Edwin