Question

Jabarkan bentuk dari : (cos a - sin a)^2

Answer 1

Verified answer

Cos^2 a - 2 cos a sin a + sin^2 a
1 - sin 2a -> Jawab

Answer 2

Verified answer

(cos a - sin a)²
= (cos a)² + 2 × (cos a) × (- sin a) + (- sin a)²
= cos² a - 2(cos a)(sin a) + sin²a

// Identitas trigonometri: cos²a + sin²a = 1
= cos² a + sin² a - 2(cos a)(sin a)
= 1 - 2(cos a)(sin a)

//Identitas trigonometri: sin 2a = 2(sin a)(cos a)
= 1 - sin 2a