Skip to content
Exercise 11.1 · Q1

Q.Integrate the following with respect to xx:

(i) x11x^{11}
(ii) 1x7\dfrac{1}{x^{7}}
(iii) x43\sqrt[3]{x^{4}}
(iv) (x5)1/8\left(x^{5}\right)^{1/8}
Tamil Nadu DgeTextbookSubjectiveImportance★★★★★
1% · 1/129 Questions
✓ Free question

Each part is a pure power of xx (after rewriting a reciprocal, a radical, or a power-of-a-power as a single exponent), so the power rule ∫xndx=xn+1n+1+c\int x^ndx=\dfrac{x^{n+1}}{n+1}+c (n≠−1n\ne-1) applies directly in every case.

Step 1. Part (i). x11x^{11} is already a single power, n=11n=11.

∫x11 dx=x1212+c.\int x^{11}\,dx=\frac{x^{12}}{12}+c.

Step 2. Part (ii). Rewrite the reciprocal power as a negative exponent: 1x7=x−7\dfrac{1}{x^7}=x^{-7}, so n=−7n=-7.

∫x−7 dx=x−6−6+c=−16x6+c.\int x^{-7}\,dx=\frac{x^{-6}}{-6}+c=-\frac{1}{6x^{6}}+c.

Step 3. Part (iii). Rewrite the cube root as a fractional exponent: x43=x4/3\sqrt[3]{x^4}=x^{4/3}, so n=43n=\tfrac43.

∫x4/3 dx=x4/3+14/3+1+c=x7/37/3+c=37x7/3+c.\int x^{4/3}\,dx=\frac{x^{4/3+1}}{4/3+1}+c=\frac{x^{7/3}}{7/3}+c=\frac37 x^{7/3}+c.

Step 4. Part (iv). A power raised to a power multiplies the exponents: (x5)1/8=x5/8\left(x^5\right)^{1/8}=x^{5/8}, so n=58n=\tfrac58.

∫x5/8 dx=x5/8+15/8+1+c=x13/813/8+c=813x13/8+c.\int x^{5/8}\,dx=\frac{x^{5/8+1}}{5/8+1}+c=\frac{x^{13/8}}{13/8}+c=\frac{8}{13}x^{13/8}+c.

Step 5. Check by differentiating. ddx ⁣(x1212)=x11\dfrac{d}{dx}\!\left(\dfrac{x^{12}}{12}\right)=x^{11} ✓; ddx ⁣(−16x6)=66x7=x−7\dfrac{d}{dx}\!\left(-\dfrac{1}{6x^6}\right)=\dfrac{6}{6x^7}=x^{-7} ✓; ddx ⁣(37x7/3)=x4/3\dfrac{d}{dx}\!\left(\dfrac37 x^{7/3}\right)=x^{4/3} ✓; ddx ⁣(813x13/8)=x5/8\dfrac{d}{dx}\!\left(\dfrac{8}{13}x^{13/8}\right)=x^{5/8} ✓ — every antiderivative differentiates back to its integrand.

✓Final answer

(i) x1212+c\dfrac{x^{12}}{12}+c (ii) −16x6+c-\dfrac{1}{6x^{6}}+c (iii) 37x7/3+c\dfrac37 x^{7/3}+c (iv) 813x13/8+c\dfrac{8}{13}x^{13/8}+c

Unlock everything free for 14 days

  • Full step-by-step solutions
  • Concept-first explanations
  • Methods, shortcuts & mistakes
  • PYQ mapping + timed mock tests

Full access for 14 days. No credit card required.