Which trigonometric function is equivalent to f(x)=sinx ?

f(x)=cos(x-3pi/2)
f(x)=cos(x-pi/2)
f(x)=cos(-x-pi/2) < -- i think this one, not sure
f(x)=cos(x+pi)

 The correct option is (B)

Step-by-step explanation:  We are given to select the correct trigonometric function that is equivalent to the following trigonometric function :

Option (A) :

Here, the given function is

So, this option is incorrect.

Option (B) :

Here, the given function is

So, this option is CORRECT.

Option (C) :

Here, the given function is

So, this option is incorrect.

Option (D) :

Here, the given function is

So, this option is incorrect.

Thus, (B) is the correct option.

step-by-step explanation:

- 2 + 10x³ - 21x² + 19x - 4

step-by-step explanation:

each term in the second factor is multiplied by each term in the first factor

x²(- 2x² + 4x - 1) - 3x(- 2x² + 4x - 1) + 4(- 2x² + 4x - 1) ← distribute

= - 2 + 4x³ - x² + 6x³ - 12x² + 3x -8x² + 16x - 4

collect like terms

= - 2 + 10x³ - 21x² + 19x - 4 ← in standard form