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$y'' + 3y' + 2y = f(t) : y(0) = 1, y'(0) = -1.$ where, $f(t) = \begin{cases} 20\cos(2t) & \frac{\pi}{4} < t < \frac{3\pi}{4} \\ 0 & Otherwise \end{cases}$ Some useful angle sum formulas for trigonometric functions are as follows: $\cos \left(\theta \pm \frac{\pi}{2}\right) = \mp \sin \theta, \cos \left(\theta \pm \frac{3\pi}{2}\right) = \pm \sin \theta ; \sin \left(\theta \pm \frac{\pi}{2}\right) = \pm \cos \theta, \sin \left(\theta \pm \frac{3\pi}{2}\right) = \mp \cos \theta.$

Name: y 3y 2y ft y0 1 y0 1 where ft begincases 20cos2t fracpi4 t frac3pi4 0 otherwise endcases some useful angle sum formulas for trigonometric functions are as follows cos lefttheta pm fracpi2rig 28763
Uploaded: 2020-02-11T10:39:58-08:00
Duration: 3 min 5 s
Channel: Matthew Allcock
Description: y 3y 2y ft y0 1 y0 1 where ft begincases 20cos2t fracpi4 t frac3pi4 0 otherwise endcases some useful angle sum formulas for trigonometric functions are as follows cos lefttheta pm fracpi2rig 28763

          $y'' + 3y' + 2y = f(t) : y(0) = 1, y'(0) = -1.$
where,
$f(t) = \begin{cases} 20\cos(2t) & \frac{\pi}{4} < t < \frac{3\pi}{4} \\ 0 & Otherwise \end{cases}$
Some useful angle sum formulas for trigonometric functions are as follows: $\cos \left(\theta \pm \frac{\pi}{2}\right) = \mp \sin \theta, \cos \left(\theta \pm \frac{3\pi}{2}\right) = \pm \sin \theta ; \sin \left(\theta \pm \frac{\pi}{2}\right) = \pm \cos \theta, \sin \left(\theta \pm \frac{3\pi}{2}\right) = \mp \cos \theta.$

$y 3y 2y ft y0 1 y0 1 where ft begincases 20cos2t fracpi4 t frac3pi4 0 otherwise endcases some useful angle sum formulas for trigonometric functions are as follows cos lefttheta pm fracpi2rig 28763$

Added by Brian O.

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