How is the Conjugate of Real Trigonometric Functions Handled?

[kolycholy]

okay, so this particular equation involves me writing conjugate of either sin or cos, but hows that possible considering they both are real in the given problem?

maybe i should convert sin and cos into their exponential form first?

but then wt would be the conjugate of this expression-----> e^2j +e^(-2j)?

 

[jpr0]

okay, so this particular equation involves me writing conjugate of either sin or cos, but hows that possible considering they both are real in the given problem?

maybe i should convert sin and cos into their exponential form first?

but then wt would be the conjugate of this expression-----> e^2j +e^(-2j)?

If you have to take the complex conjugate of a real quantity, say z, then z is its own complex conjugate, i.e. z=z^{\ast}. This follows from the fact that the real part of a complex number and the real part of its conjugate are always the same by definition:

<br /> z = x + iy<br />
<br /> z^{\ast} = x - iy<br />

where x\,,y are real.