Determine the rms value for the given function

[Northbysouth]

Homework Statement

Determine the rms value of v(t) = 15 + 10cos(20πt)

Homework Equations

V_rms = √(1/T*∫^T₀v²dt

The Attempt at a Solution

√(10*∫^0.1₀[15+10cos(20πt)]²dt

Unless, I'm much mistaken I should be able to plug the equation into the formula I have given above. I used the integral function on my calculator to do the calculation and I got 24.98V but the answer is supposed to be 16.58V

Any suggestions for where I'm going wrong?

 

[TSny]

Your setup is correct. You must have made a mistake in the integration with your calculator.

 

[Bob Le]

Vrms = √15^2+(10/√2)^2 = 16.58 V