Sunday
March 26, 2017

Post a New Question

Posted by on .

what are the amplitude and period of the sinusoid y=6cosx+7sinx?

  • pre cal - ,

    We could write 6cosx + 7sinx as a single
    sine function of the form asin(x + A)

    asin(x+A) = asinxcosA + acosxsinA = 7sinx + 6cosx
    let x=0
    ---> asinA = 6 or sinA = 6/a
    let x=π/2
    ---> acosA = 7 or cosA = 7/a
    but sin^2 A + cos^2 B = 1
    36/a^2 + 49/a^2 = 1
    a^2 = 85
    a =√85

    so the amplitude is √85
    and the period is 2π, (A is simply a phase shift)

Answer This Question

First Name:
School Subject:
Answer:

Related Questions

More Related Questions

Post a New Question