SOLUTION: if tan A>0 and (tan A)(sin A)>0, in what quadrant does angle A lie?

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Question 1156807: if tan A>0 and (tan A)(sin A)>0, in what quadrant does angle A lie?
Found 3 solutions by Boreal, Alan3354, MathLover1:
Answer by Boreal(15235) About Me  (Show Source):
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tan A >0 in the first and third quadrants (it is sin/cos)
sin A >0 in the first and third quadrants
the product is positive and is in the first quadrant.
In the third quadrant tan A is positive because sin A is - and cos A is -. Their quotient is positive,but if multiplied by the - sin A in the third quadrant, that product would be negative.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
if tan A>0 and (tan A)(sin A)>0, in what quadrant does angle A lie?
============
Quad   1   2   3   4
sin    +   +   -   -
tan    +   -   +   -


Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

if tan%28A%29%3E0 and %28tan%28A%29%29%28sin%28A%29%29%3E0, in what quadrant does angle+A lie?
if tan%28A%29%3E0, means only if sin%28A%29%3E0 this statement %28tan%28A%29%29%28sin%28A%29%29%3E0 will be true

trig-functions.jpg

sin%28A%29 is positive in Q1 and Q2
tan%28A%29 is positive in Q1 and Q3
Therefore A must be in Q1.