Question

Compute ∫cos(x)-\(\frac {3}{x4}\)dx.

(a) sin(x)+\(\frac {3}{4}\)x^-7+c

(b) sec(x)+\(\frac {3}{4}\)x^-3+c

(c) sin(x)+\(\frac {3}{4}\)x^-3

(d) sin(x)+\(\frac {3}{4}\)x^-3+c

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This interesting question is from Definite Integral in portion Integrals of Mathematics – Class 12

Answer 1

Correct answer is (d) sin(x)+\(\frac {3}{4}\)x^-3+c

For explanation: ∫cos(x)-\(\frac {3}{x4}\)dx = ∫cos(x) dx−∫3(x^-4) dx

= sin(x)+\(\frac {3}{4}\)x^-3+c