Question

four quadrant and sign conventions

Answer 1

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good afternoon_________✌️✌️


1. In Quadrant I, x > 0, y > 0 (+x,+y)

2. In Quadrant II, x < 0, y > 0 (-x,+y)

3 . In Quadrant III, x < 0, y < 0 (-x,-y)

4. In Quadrant IV, x > 0, y < 0 (+x,-y)




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AJay
B.tech, IIT BHU

Answer 2

There are 4 quadrants. we measure angles from positive x axis. there is a rule called ASTC rule to represent sign convention of trigonometric ratios.
you can remember the rule as ADD SUGAR TO COFFEE.

1st quadrant - A- All are positive

2nd quadrant- S- sin and it's reciprocal cosec are positive.

3rd quadrant- T- Tan and its reciprocal cot are positive.

4th quadrant- C - Cos and it's reciprocal sec are positive.
every ratio is positive in two quadrants and negative in two quadrants.