Question

sin 15 °+ sin 30°+ sin 45°- cos 60°- cos 75°- cos 90°

Answer 1

hope it helps you........

Answer 2

Answer:

☆ QUESTION ☆

sin 15 °+ sin 30°+ sin 45°- cos 60°- cos 75°- cos 90°

☆ ANSWER ☆

SIN A = COS (90-A)

COS A = SIN (90-A)

THEREFORE ;

COS 75 + COS 60 + COS 45 - COS 60 - COS 75 - COS 90

= COS 45

= 1/ROOT2

HOPE THAT HELPS

☆ EXTRA ☆

• THESE ARE CALLED TRIGONOMETRY FORMULAS.
• THERE IS ALSO A TABLE FOR THE DEGREES OF ALL THE SIN AND COS .

HOPE THAT HELPS