Question

sin 270 degrees =-1 prove​

Answer 1

Answer:

$sin \: {270}^{0} = sin \: ( {180}^{0} + {90}^{0} ) \\ = - sin \: {90}^{0} = - 1 \\ hence \\ \: sin \: {270}^{0} = \: - 1$

Answer 2

Step-by-step explanation:

In the above figure which is also called the cast rule

sin270 is in 3rd or 4th quadrant

therefore

sin 270°will be equal to sin (90+180)° = -sin90=-1

thank you