Identify Integral: Identify the integral to be solved.We need to evaluate the integral of the function x5+12x4 from x=21 to x=2.
Simplify Integral: Simplify the integral if possible.In this case, the integral does not simplify easily, so we proceed with the given integral.
Perform Substitution: Perform a substitution if applicable.Let u=x5+1, then du=5x4dx. We need to adjust the integral to match this substitution. To do this, we multiply and divide the integral by 5 to get the x4 term to match du.
Rewrite in terms of u: Rewrite the integral in terms of u.The integral becomes 52∫(21)22x5+15x4dx=52∫u(21)u(2)udu.
Update Limits: Update the limits of integration.When x=21, u=(21)5+1=321+1=3233.When x=2, u=25+1=32+1=33.
Evaluate Integral: Evaluate the integral with the new limits.The integral is now (52)∫323333udu. The integral of u1 with respect to u is ln∣u∣, so we have (52)[ln∣u∣] from u=3233 to u=33.
Calculate Definite Integral: Calculate the definite integral. Plug in the limits of integration: (52)⋅(ln∣33∣−ln∣3233∣)=(52)⋅(ln(33)−ln(33)+ln(32))=(52)⋅ln(32).
Simplify Result: Simplify the result.The final answer is (52)⋅ln(32). Since 32=25, we can use the property of logarithms that ln(ab)=b⋅ln(a) to simplify further: (52)⋅ln(25)=(52)⋅5⋅ln(2)=2⋅ln(2).
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