Can plz you list the formulae of function change while putting ((pie/2) - x ) like
sin(pie/2 - x) = sin x
cos (pie/2 - x) = - sin x
something like that.
Also, explain it using graph (4 quadrant system, All +ve in 1st quad, Sin +ve in 2 quad, T in 3rd, C in 4th quad method)
Means how I use this ASTC for help in these formulae.
By which formula do we get - sin x or - cos x
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.
These relationships (and the ones I have you before) can be worked out in several ways:
- Using the unit circle and the four quadrants; or
- Using the graphs of ; or
- Using the addition formulae for sine and cosine; for example:
Grandad, etcand then using facts like , etc.