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The differential equation, find a particular solution satisfying the given condition : \(\frac{dy}{dx}\) = y tan x, it being given that y = 1 when x = 0. |
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Answer» Rearranging the terms we get: \(\frac{dy}y\) = tan x dx ⇒ \(\int\frac{dy}y\) = \(\int{tanx}\,dx\) + c ⇒ log |y| = log |sec x| + log c ⇒ log |y| - log |sec x| = log c ⇒ log |y| + log |cos x| = log c ⇒ y cos x = c y = 1 when x = 0 ∴1 × cos0 = c ∴c = 1 ⇒ y cos x = 1 ⇒ y = 1/cos x ⇒ y = sec x Ans: y = sec x |
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