Simplify and Substitute: Simplify the integral if possible.We have the integral ∫x23−49x14dx. We can simplify the denominator by factoring out the common term x, which is x21.x23−49x=x(x−49)Now, the integral becomes ∫x(x−49)14dx.
Alternative Substitution: Perform a substitution.Let u=x−49, then dxdu=1, so dx=du.When x=49, u=0. We need to change the x in terms of u as well.Since u=x−49, x=u+49, and x=u+49.Now, substitute into the integral: dxdu=10.
New Simplification: Split the integral into two parts if possible.The integral ∫u+49⋅u14du is difficult to integrate as it is. However, we can split it into two separate integrals by dividing 14 by the product u+49⋅u.This step is not applicable here as the integral does not simplify easily into two separate integrals. We need to find another method to solve this integral.
Partial Fraction Decomposition: Look for an alternative substitution or method.The substitution made in Step 2 does not seem to simplify the integral enough for us to integrate easily. We need to consider a different approach.Let's go back to the original integral and try a different substitution.Let's try the substitution u=x1/2, which implies x=u2 and dx=2udu.Now, substitute into the integral: ∫u3−49u14⋅2udu.
Integrate with Fractions: Simplify the integral with the new substitution.We have the integral ∫(14⋅2u)/(u3−49u)du.This simplifies to ∫(28u)/(u(u2−49))du.We can cancel out a u from the numerator and denominator: ∫(28)/(u2−49)du.Now, we have a difference of squares in the denominator: u2−49=(u−7)(u+7).
Final Integration: Perform partial fraction decomposition.We can express u2−491 as u−7A+u+7B.Multiplying both sides by (u2−49), we get 1=A(u+7)+B(u−7).Setting u=7, we find that A=141. Setting u=−7, we find that B=−141.Now, the integral becomes ∫(28⋅(141)/(u−7)−141/(u+7))du.
Final Integration: Perform partial fraction decomposition.We can express u2−491 as u−7A+u+7B.Multiplying both sides by (u2−49), we get 1=A(u+7)+B(u−7).Setting u=7, we find that A=141. Setting u=−7, we find that B=−141.Now, the integral becomes ∫(28⋅(141)/(u−7)−141/(u+7))du.Integrate using the partial fractions.The integral is now ∫(u−72−u+72)du.This integrates to u−7A+u+7B0.
Final Integration: Perform partial fraction decomposition.We can express u2−491 as u−7A+u+7B.Multiplying both sides by (u2−49), we get 1=A(u+7)+B(u−7).Setting u=7, we find that A=141. Setting u=−7, we find that B=−141.Now, the integral becomes ∫(28⋅(141)/(u−7)−141/(u+7))du.Integrate using the partial fractions.The integral is now ∫(u−72−u+72)du.This integrates to u−7A+u+7B0.Substitute back to the original variable u−7A+u+7B1.Recall that u−7A+u+7B2, so the integral becomes u−7A+u+7B3.
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