- #1
utsav55
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Homework Statement
Can you please list the formulae of function change while putting (pie/2 - x) and adding or subtracting 2Pie
Basicly, I need help on 2 formulae. One is add/subtract Pie/2 and the other is add/subtract 2Pie.
Homework Equations
sin (pie/2 - x) = sin x
cos (pie/2 - x) = - sin x
sin (2Pie - x) = -cos x
something like that... Its just example, may not be correct.
The Attempt at a Solution
I know a little something that All is +ve in first quadrant, only sin is +ve in 2nd quad, tan in 3rd and cos in 4th quad.
Maybe we can use this to determine +ve or -ve sin/cos when we add or subtract 2Pie or Pie.