Home › MHT-CET › Mathematics › Definite Integration › Using definite integration as the limit of a sum…
Using definite integration as the limit of a sum, $\int_1^2 (2x + 5)\,dx$ equals:
A$6$
B$8$
C$10$
D$12$
Answer & Solution
Correct answer: B. $8$
Direct evaluation: $[x^2 + 5x]_1^2 = (4 + 10) - (1 + 5) = 14 - 6 = 8$. (The limit-of-sum approach in the textbook yields the same: $\lim_n h\sum(7 + 2rh) = 7(1) + (1)(1+0) = 8$.)
Related questions
$\int_0^{\pi/2} \cos^2 x\,dx$ equals:$\int_0^{\pi/2} qrt{1 - \cos 4x}\,dx$ equals:Using the King's property, evaluate $\int_0^{\pi/2} \dfrac{dx}{1 + qrt[3]{\tan x}}$:$\int_1^2 \dfrac{\log x}{x^2}\,dx$ equals:$\int_{-1}^{1} |5x - 3|\,dx$ equals:Evaluate $\int_2^3 7^x\,dx$:$\int_0^4 (x - x^2)\,dx$ equals:$\int_0^1 e^x\,dx$ equals: