Q. Given tanA=−6011 and that angle A is in Quadrant IV, find the exact value of cscA in simplest radical form using a rational denominator.
Given Information: We are given that tanA=−6011 and that angle A is in Quadrant IV. In the fourth quadrant, the tangent function is negative because sine is negative and cosine is positive. We can use the Pythagorean identity for tangent, which is tan2A+1=sec2A, to find secA and then use that to find cscA.
Find sec A: First, let's find sec A using the identity tan2A+1=sec2A. We substitute tanA with −(11/60) to find sec2A.sec2A=tan2A+1sec2A=(−11/60)2+1sec2A=(121/3600)+1sec2A=(121/3600)+(3600/3600)sec2A=(121+3600)/3600sec2A=3721/3600
Find cscA: Now, we take the square root of sec2A to find secA. Since A is in the fourth quadrant, secA will be positive.secA=36003721secA=36003721secA=6061
Find cosA: The cosecant function is the reciprocal of the sine function, so cscA=sinA1. Since secA is the reciprocal of cosA, and we have the Pythagorean identity sin2A+cos2A=1, we can find sinA using the relationship sin2A=1−cos2A.
Find sinA: We know that cosA=secA1, so we can find cosA first.cosA=secA1cosA=60611cosA=6160
Find cscA: Now we use the identity sin2A+cos2A=1 to find sin2A. sin2A=1−cos2A sin2A=1−(6160)2 sin2A=1−(37213600) sin2A=(37213721)−(37213600) sin2A=37213721−3600 sin2A=3721121
Find cscA: Now we use the identity sin2A+cos2A=1 to find sin2A. sin2A=1−cos2A sin2A=1−(6160)2 sin2A=1−(37213600) sin2A=(37213721)−(37213600) sin2A=37213721−3600 sin2A=3721121We take the square root of sin2A to find sin2A+cos2A=10. Since sin2A+cos2A=11 is in the fourth quadrant, sin2A+cos2A=10 will be negative. sin2A+cos2A=13 sin2A+cos2A=14 sin2A+cos2A=15
Find cscA: Now we use the identity sin2A+cos2A=1 to find sin2A. sin2A=1−cos2A sin2A=1−(6160)2 sin2A=1−(37213600) sin2A=(37213721)−(37213600) sin2A=37213721−3600 sin2A=3721121We take the square root of sin2A to find sin2A+cos2A=10. Since sin2A+cos2A=11 is in the fourth quadrant, sin2A+cos2A=10 will be negative. sin2A+cos2A=13 sin2A+cos2A=14 sin2A+cos2A=15Finally, we find cscA, which is the reciprocal of sin2A+cos2A=10. sin2A+cos2A=18 sin2A+cos2A=19 sin2A0
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