Q. We are given thatdxdy=1−y2. Find an expression for dx2d2y in terms of x and y.dx2d2y=
Given Derivative: We are given the first derivative of y with respect to x as dxdy=1−y2. To find the second derivative, we need to differentiate dxdy with respect to x.
Apply Chain Rule: Using the chain rule, we differentiate dxdy with respect to x. Since y is a function of x, we treat y as a function y(x) and apply the chain rule accordingly.\frac{d^{\(2\)}y}{dx^{\(2\)}} = \frac{d}{dx} \left(\frac{dy}{dx}\right) = \frac{d}{dx} \left(\sqrt{\(1\) - y^{\(2\)}}\right)
Differentiate \(\sqrt{1 - y^2}: To differentiate 1−y2, we use the chain rule again. Let u=1−y2, then the derivative of u with respect to u is (21)u−21.dxd(1−y2)=dxd(u)⋅dydu⋅dxdy
Find dydu: Now we find dydu, which is the derivative of u=1−y2 with respect to y.dydu=dyd(1−y2)=−2y
Substitute and Simplify: Substitute dydu into the previous expression and simplify.dxd(1−y2)=(21)(1−y2)−21⋅(−2y)⋅(dxdy)
Substitute dxdy: We already know that dxdy=1−y2, so we substitute this into the expression.dx2d2y=21(1−y2)−21⋅(−2y)⋅1−y2
Simplify Expression: Simplify the expression by multiplying the terms together.dx2d2y=−y(1−y2)−21×(1−y2)21
Final Result: Since (1−y2)−21⋅(1−y2)21 equals 1, the expression simplifies to: dx2d2y=−y
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