Finding dy/dx of a function when x is the subject...?
I have the equation here but I want to solve it myself so I will give a different example...
Find dy/dx of x=sin2y
I have the equation here but I want to solve it myself so I will give a different example...
Find dy/dx of x=sin2y
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one trick you can use is to find dx/dy
in your given equation dx/dy = 2cos2y
now we know that dy/dx *dx/dy = 1
this is true because
dy/dy *dx/dx = 1*1 = 1
now this means that dy/dx = 1/(dx/dy)
so you found dx/dy
so dy/dx = 1/(2cos2y)
its not always neat but it does work
in your given equation dx/dy = 2cos2y
now we know that dy/dx *dx/dy = 1
this is true because
dy/dy *dx/dx = 1*1 = 1
now this means that dy/dx = 1/(dx/dy)
so you found dx/dy
so dy/dx = 1/(2cos2y)
its not always neat but it does work
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you can use implicit differentiation
x = sin2y
Take derivative of both sides. On the LHS you will have d/dx (x) which is 1. and on the RHS you can use chain rule:
d/dx(x) = d/dx(sin2y)
1 = cos2y * [d/dx (2y)]
1 = cos2y * 2 dy/dx
dy/dx = 1/(2cos2y)
If you want to write it in terms of x,
dy/dx = 1/[2√(1-x²)]
(because cos²(2y) = 1-sin²(2y) )
or you can rewrite your equation as
2y = sinˉ¹(x)
y = (1/2)sinˉ¹(x)
y ' = 1/[2√(1-x²)]
x = sin2y
Take derivative of both sides. On the LHS you will have d/dx (x) which is 1. and on the RHS you can use chain rule:
d/dx(x) = d/dx(sin2y)
1 = cos2y * [d/dx (2y)]
1 = cos2y * 2 dy/dx
dy/dx = 1/(2cos2y)
If you want to write it in terms of x,
dy/dx = 1/[2√(1-x²)]
(because cos²(2y) = 1-sin²(2y) )
or you can rewrite your equation as
2y = sinˉ¹(x)
y = (1/2)sinˉ¹(x)
y ' = 1/[2√(1-x²)]
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You differentiate implicitly. I won't go into much detail as to why it works, but if you are interested I suggest reading the chapter on your calculus book.
dy/dx of x = sin2y
1 = 2cos(2y)(dy/dx)
dy/dx = (1/2)cos(2y)
dy/dx of x = sin2y
1 = 2cos(2y)(dy/dx)
dy/dx = (1/2)cos(2y)
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I'd solve for y:
y = (1/2) arcsin(x) + n*pi
and then take dy/dx:
dy/dx [(1/2) arcsin(x) + n*pi] = 0.5/(square root(1- x^2))
y = (1/2) arcsin(x) + n*pi
and then take dy/dx:
dy/dx [(1/2) arcsin(x) + n*pi] = 0.5/(square root(1- x^2))
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nothin to do hard wrk......simply fine dx/dy thn inverse ur answer u will get dy/dx....esy wayyy
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you treat x as a constant therefore dy/dx of x is just 0.