Mathematics

Mathematics

Problem

Consider the function g(x)=x5g(x)=x^{5}. Provide a complete verification that the derivative of gg at an arbitrary point xx satisfies g′(x)=5x4g'(x)=5x^{4}. Your response must rely solely on algebraic manipulation and limit evaluation. (a) Write the difference quotient expression that defines g′(x)g'(x). (b) Expand (x+h)5(x+h)^{5} using an appropriate algebraic theorem, and organize the result so that all terms are visible. (c) Simplify the numerator of the difference quotient, factor out all common factors of hh, and write the resulting fraction. (d) Evaluate the limit as h→0h\to 0 and state the final formula for g′(x)g'(x), explicitly explaining why every term except one vanishes in the limit.

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