- #1

NutriGrainKiller

- 62

- 0

[tex] \int_{0}^{2 \lambda} \cos({\frac{kx}{2}}) \cos({nx}) dx[/tex]

I can't find my calc2 notes and it's killing me! This thing came up half way through the computation of the Fourier series of [tex]f(x) = A\cos({\frac{\pi x}{\lambda}})[/tex]..and i can't remember how to do it!

I am very aware of the trig identity below, but i would prefer not to use it for obvious reasons.

[tex]\cos{\alpha}\cos{\beta} = \frac{1}{2}[\cos{\frac{(\alpha + \beta)}{2} + \cos{\frac{(\alpha - \beta)}{2}][/tex]

I have the exact same question except instead of two cosines there's one cosine and one sine..any help is appreciated!

I can't find my calc2 notes and it's killing me! This thing came up half way through the computation of the Fourier series of [tex]f(x) = A\cos({\frac{\pi x}{\lambda}})[/tex]..and i can't remember how to do it!

I am very aware of the trig identity below, but i would prefer not to use it for obvious reasons.

[tex]\cos{\alpha}\cos{\beta} = \frac{1}{2}[\cos{\frac{(\alpha + \beta)}{2} + \cos{\frac{(\alpha - \beta)}{2}][/tex]

I have the exact same question except instead of two cosines there's one cosine and one sine..any help is appreciated!

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