Cos (3A) = 4 Cos³A - 3 CosA

By -
Cos (3A) = 4 Cos³A - 3 CosA?

Comments

Post a Comment

Comment here

Popular posts from this blog

Trigonometric values w.r.t. Quadrants (1st, 2nd, 3rd and 4th)

By -
Image
👉Important Rules for trigonometric values in 1st ,2nd ,3rd and 4th Quadrant. {1}.    Quadrant 1st: (90°-θ) and (360°+θ) All Trigonometric values are Positive (+). {2}. Quadrant 2nd :  (90°+θ) and (180°-θ) Only values of sine (sin) and Cosecant (cosec) is positive (+) rest all Trigonometric values are negative (-). {3}. Quadrant 3rd:  (180°+θ) and (270°-θ) Only values of tangent (tan) and Cotangent (cot) is positive (+) rest all Trigonometric values are negative (-). {4} . Quadrant 4th :  (270°+θ) and (360° -θ) Only values of cosine (cos) and Secant (sec) is positive (+) rest all Trigonometric values are negative (-). 👇 The picture showing the values of all Trigonometric ratios in different quadrants :- # A Simple Way to remember A DD : All values positive S UGAR : Sine,Cosine are positive T O : Tan, cot are positive C OFEE : cos ,sec are positive
Click here to read

How Sin²θ + Cos²θ = 1?

By -
Image
How   Sin²θ + Cos²θ = 1...?? According to Pythagoras theorem, "the square of hypotenuse(H) is equal to the sum of square of base(B) and perpendicular(P)" i.e.     H² = B² + P² (Dividing both sides by H²) we get,     H²/H² = B²/H² + P²/H²        1   = Sin²θ + Cos²θ                       ....(B/H  = sinθ and P/H = cosθ) Hence, Sin²θ + Cos²θ = 1 How Sin²θ + Cos²θ = 1?
Click here to read