Find the particular solution of the following differential equation ("d"y)/("d"x) = e2y cos x, when x = pi/6, y = 0. Solution: The given D.E. is ("d"y)/("d"x) = e2y cos x - Mathematics and Statistics

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Find the particular solution of the following differential equation

`("d"y)/("d"x)` = e2y cos x, when x = `pi/6`, y = 0.

Solution: The given D.E. is `("d"y)/("d"x)` = e2y cos x

∴ `1/"e"^(2y)  "d"y` = cos x dx

Integrating, we get

`int square  "d"y` = cos x dx

∴ `("e"^(-2y))/(-2)` = sin x + c1

∴ e–2y = – 2sin x – 2c1

∴ `square` = c, where c = – 2c

This is general solution.

When x = `pi/6`, y = 0, we have

`"e"^0 + 2sin  pi/6` = c

∴ c = `square`

∴ particular solution is `square`

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Solution

The given D.E. is `("d"y)/("d"x)` = e2y cos x

∴ `1/"e"^(2y)  "d"y` = cos x dx

Integrating, we get

`int bb("e"^(-2y))  "d"y` = cos x dx

∴ `("e"^(-2y))/(-2)` = sin x + c1

∴ e–2y = – 2sin x – 2c1

e–2y + 2sin x = c, where c = – 2c

This is general solution.

When x = `pi/6`, y = 0, we have

`"e"^0 + 2sin  pi/6` = c

∴ `1 +  2(1/2)` = c

∴ c = 2 

∴ particular solution is e–2y + 2sin x = 2 

  Is there an error in this question or solution?
Chapter 1.8: Differential Equation and Applications - Q.6

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