Solving derivative- possible without quotient rule?

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SUMMARY

The discussion focuses on finding the derivative of the function d/dx [g(x + 1)(√(2 + (x + 8)^(1/3))/(cos(tan(sin(tan(sin x))))] at x = 0. The original attempt involved using the quotient rule, leading to the expression (a'x*bx + b'x*ax)(cx)-c'x*px*qx)/cx^2, which simplifies to 2*g'(1) when evaluated at x = 0. An alternative method proposed is to avoid the quotient rule by multiplying by sec(cos(...)), thus allowing the use of the product rule instead.

PREREQUISITES
  • Understanding of derivatives and differentiation rules, particularly the product and quotient rules.
  • Familiarity with trigonometric functions and their derivatives, specifically secant and cosine.
  • Knowledge of function notation and how to denote derivatives clearly, such as a'(x) instead of a'x.
  • Basic algebraic manipulation skills to simplify complex expressions.
NEXT STEPS
  • Learn about the product rule and its applications in calculus.
  • Study the secant function and its relationship to cosine in differentiation.
  • Practice rewriting complex derivatives to improve clarity and understanding.
  • Explore alternative methods for finding derivatives without relying on the quotient rule.
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Students studying calculus, particularly those learning about differentiation techniques, as well as educators looking to clarify derivative concepts without using the quotient rule.

Persimmon
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Homework Statement


find the following derivative
d/dx [g(x + 1)(√(2+ (x + 8)^(1/3))/(cos(tan(sin(tan(sin x))))]
at x = 0

Homework Equations





The Attempt at a Solution



I split the big long derivative into 3 functions:
a(x) = g(x + 1)
b(x) = √(2+ (x + 8)^(1/3))
c(x) = cos(tan(sin(tan(sin x))))

and got : (a'x*bx + b'x*ax)(cx)-c'x*px*qx)/cx^2
subbing in x = 0 that simplified into 2*g'(1)
but it was mentioned that it's possible to solve this without the quotient rule. I can't figure out how you would solve this derivative if you didn't use the quotient rule.
 
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Persimmon said:

Homework Statement


find the following derivative
d/dx [g(x + 1)(√(2+ (x + 8)^(1/3))/(cos(tan(sin(tan(sin x))))]
at x = 0

Homework Equations





The Attempt at a Solution



I split the big long derivative into 3 functions:
a(x) = g(x + 1)
b(x) = √(2+ (x + 8)^(1/3))
c(x) = cos(tan(sin(tan(sin x))))

and got : (a'x*bx + b'x*ax)(cx)-c'x*px*qx)/cx^2
subbing in x = 0 that simplified into 2*g'(1)
but it was mentioned that it's possible to solve this without the quotient rule. I can't figure out how you would solve this derivative if you didn't use the quotient rule.
Instead of dividing by cos(...), you can multiply by sec(...). That way you're set up to use the product rule.

BTW, your notation is not very helpful.
a'x*bx + b'x*ax)(cx)-c'x*px*qx)/cx^2
As written this looks like a' * x * b * x etc. To be clearer, write a'(x) * b(x) etc.
 
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Sorry for the unclear notation. I was trying to make it clearer so there wouldn't be endless brackets but I guess it's even more confusing that way. Thank you for your help!
 

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