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Find dydxif,x+y=a - Mathematics and Statistics

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Question

Find `"dy"/"dx" if, sqrt"x" + sqrt"y" = sqrt"a"`

Sum
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Solution

`sqrt"x" + sqrt"y" = sqrt"a"`

Differentiating both sides w.r.t. x, we get

`1/(2 sqrt"x") + 1/(2sqrt"y") * "dy"/"dx" = 0`

∴ `1/(2sqrt"y") * "dy"/"dx" = (-1)/(2sqrt"x")`

∴ `"dy"/"dx" = - sqrt("y"/"x")`

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Chapter 3: Differentiation - EXERCISE 3.4 [Page 95]

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