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If y = tanx + secx, prove that ddd2ydx2=cosx(1-sinx)2 - Mathematics

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प्रश्न

If y = tanx + secx, prove that `("d"^2y)/("d"x^2) = cosx/(1 - sinx)^2`

योग

उत्तर

We have y = tanx + secx.

Differentiating w.r.t. x, we get

`("d"y)/("d"x)` = sec2x + secx tanx

= `1/(cos2x) + sinx/(cos^2x)`

= (1 + sinx)/(cos^2x)`

= `(1 + sinx)/((1 + sinx)(1 - sinx))`

Thus `("d"y)/("d"x) = 1/(1 - sin )`.

Now, differentiating again w.r.t. x, we get

`("d"^2y)/("d"x^2) = (-(cos x))/(1 - sin x)^2`

= `cosx/(1 - sin x)^2`

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अध्याय 5: Continuity And Differentiability - Solved Examples [पृष्ठ ९६]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
अध्याय 5 Continuity And Differentiability
Solved Examples | Q 14 | पृष्ठ ९६

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