Question

why is sin 90=1 or cos 90=0

Answer 1

sin90°=cos(90-90)
          =cos0°
          =1

cos90°=sin(90-90)
          =sin0°
          =0

Answer 2

Heya !!!




We know that,


Cos0° = 1

Sin0° = 0

Sin(90°- Theta) = Cos theta




Sin theta = Cos (90° - Theta)


Cos(90° - Theta ) = Sin theta


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Therefore,


Sin 90° = Cos (90°-90°)





Sin90° = Cos0°



Sin90° = 1



And,


Cos(90° - Theta ) = Sin theta



Cos90° = Sin(90°-90°)



Cos90° = Sin0°

Hence,




Cos 90° = 0



HOPE IT WILL HELP YOU...... :-)