SOLUTION: How to find a value of tan x without using calculator if x is obtuse angle and 2(sec²x-1)=5secx+10 ?

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Question 1169243: How to find a value of tan x without using calculator if x is obtuse angle and 2(sec²x-1)=5secx+10 ?
Answer by Solver92311(821) About Me  (Show Source):
You can put this solution on YOUR website!


Solve the quadratic in . Since the angle is obtuse (i.e. the terminal ray is in QII), the cosine and its reciprocal are negative. Discard the positive root and take the reciprocal of the negative root giving you . Then use the Pythagorean identity, to find (remember, sine is positive in QII). Then calculate


John

My calculator said it, I believe it, that settles it

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