If the cost function of a product is given by C(x) = 3/4x^2 - 5x + 21, then the marginal cost when x = 10 is Option 1: 10 Option 2: 21 Option 3: 16 Option 4: 5

Answer: 10. Solution: The marginal cost is the derivative of the cost function. Given cost function: C(x) = 3/4x^2 - 5x + 21 Differentiating each term: C'(x) = 3/4 x 2x - 5 + 0 C'(x) = 3/2x - 5 Substituting x = 10: C'(10) = 3/2 x 10 - 5 C'(10) = 30/2 - 5 C'(10) = 15 - 5 C'(10) = 10 Therefore, the marginal cost when x = 10 is 10.

Calculus

Application of Derivatives

Easy

applied

If the cost function of a product is given by $C(x) = \frac{3}{4}x^2 - 5x + 21$ , then the marginal cost when $x = 10$ is

✅ Correct Option: 1

The marginal cost is the derivative of the cost function.

Given cost function:

$C(x) = \frac{3}{4}x^2 - 5x + 21$

Differentiating each term:

$C'(x) = \frac{3}{4} \times 2x - 5 + 0$

$C'(x) = \frac{3}{2}x - 5$

Substituting $x = 10$ :

$C'(10) = \frac{3}{2} \times 10 - 5$

$C'(10) = \frac{30}{2} - 5$

$C'(10) = 15 - 5$

$C'(10) = 10$

Therefore, the marginal cost when $x = 10$ is $10$ .

2026: 22 May Shift 2

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Match List-I with List-II

List-I	List-II
(A) The maximum value of $f(x) = \sin(3x) + 6$	(I) 2
(B) The maximum value of $f(x) = -\vert x + 2\vert + 4$	(II) 5
(C) The minimum value of $f(x) = (3x + 1)^2 + 5$	(III) 7
(D) The minimum value of $f(x) = 2 \cos x + 4$	(IV) 4

Choose the correct answer from the options given below:

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If the cost function of a product is given by C(x)=34x2−5x+21C(x) = \frac{3}{4}x^2 - 5x + 21C(x)=43​x2−5x+21, then the marginal cost when x=10x = 10x=10 is

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CUET Mathematics Past Year Questions (Topic-Wise)

If the cost function of a product is given by $C(x) = \frac{3}{4}x^2 - 5x + 21$ , then the marginal cost when $x = 10$ is