English

Find the second order derivatives of the following : x3.logx

Advertisements
Advertisements

Question

Find the second order derivatives of the following : x3.logx

Sum
Advertisements

Solution

Let y = x3.logx

Then, `"dy"/"dx" = "d"/"dx"(x^3.logx)`

= `x^3"d"/"dx"(logx) + (logx)."d"/"dx"(x^3)`

= `x^3 xx (1)/x + (logx) xx 3x^2`

= x2 + 3x2 log x
= x2(1 + 3 log x)
and
`(d^2y)/(dx^2) = "d"/"dx"[x^2(1 + 3logx)]`

= `x^2."d"/"dx"(1 + 3logx) + (1 + 3logx) xx 2x`

= `x^2(0 + 3 xx 1/x) + (1 + 3logx) xx 2x`

= 3x + 2x + 6x log x
= 5x + 6x log x 
= x(5 + 6 log x).

shaalaa.com
  Is there an error in this question or solution?
Chapter 1: Differentiation - Exercise 1.5 [Page 60]

RELATED QUESTIONS

Differentiate the function with respect to x.

(log x)cos x


Differentiate the function with respect to x.

`(sin x)^x + sin^(-1) sqrtx`


Differentiate the function with respect to x.

xsin x + (sin x)cos x


Differentiate the function with respect to x.

`x^(xcosx) + (x^2 + 1)/(x^2 -1)`


Find `bb(dy/dx)` for the given function:

(cos x)y = (cos y)x


Differentiate the function with respect to x:

xx + xa + ax + aa, for some fixed a > 0 and x > 0


If cos y = x cos (a + y), with cos a ≠ ± 1, prove that `dy/dx = cos^2(a+y)/(sin a)`.


If ey ( x +1)  = 1, then show that  `(d^2 y)/(dx^2) = ((dy)/(dx))^2 .`


Find `dy/dx` if y = x+ 5x


Find `(d^2y)/(dx^2)` , if y = log x


Find `"dy"/"dx"` if y = xx + 5x


If y = (log x)x + xlog x, find `"dy"/"dx".`


If log (x + y) = log(xy) + p, where p is a constant, then prove that `"dy"/"dx" = (-y^2)/(x^2)`.


If xy = ex–y, then show that `"dy"/"dx" = logx/(1 + logx)^2`.


If y = `x^(x^(x^(.^(.^.∞))`, then show that `"dy"/"dx" = y^2/(x(1 - logy).`.


If x = a cos3t, y = a sin3t, show that `"dy"/"dx" = -(y/x)^(1/3)`.


If x = sin–1(et), y = `sqrt(1 - e^(2t)), "show that"  sin x + dy/dx` = 0


Choose the correct option from the given alternatives :

If xy = yx, then `"dy"/"dx"` = ..........


If y = A cos (log x) + B sin (log x), show that x2y2 + xy1 + y = 0.


If f(x) = logx (log x) then f'(e) is ______


If y = log [cos(x5)] then find `("d"y)/("d"x)`


If y = `log[sqrt((1 - cos((3x)/2))/(1 +cos((3x)/2)))]`, find `("d"y)/("d"x)`


If y = 5x. x5. xx. 55 , find `("d"y)/("d"x)`


If x7 . y5 = (x + y)12, show that `("d"y)/("d"x) = y/x`


If y = `(sin x)^sin x` , then `"dy"/"dx"` = ?


Derivative of loge2 (logx) with respect to x is _______.


lf y = `2^(x^(2^(x^(...∞))))`, then x(1 - y logx logy)`dy/dx` = ______  


If xy = ex-y, then `"dy"/"dx"` at x = 1 is ______.


`8^x/x^8`


`log (x + sqrt(x^2 + "a"))`


`log [log(logx^5)]`


`lim_("x" -> -2) sqrt ("x"^2 + 5 - 3)/("x" + 2)` is equal to ____________.


If y = `x^(x^2)`, then `dy/dx` is equal to ______.


If `log_10 ((x^2 - y^2)/(x^2 + y^2))` = 2, then `dy/dx` is equal to ______.


Find `dy/dx`, if y = (sin x)tan x – xlog x.


Find `dy/dx`, if y = (log x)x.


Evaluate:

`int log x dx`


For which type of function is logarithmic differentiation especially useful?


What is the first step in the standard procedure for \[y=[u(x)]^{v(x)}\]?


After taking logarithms in logarithmic differentiation, which rules are used to simplify products, quotients and powers before differentiation?


Which derivative correctly represents differentiating \[\ln y\] carefully?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×