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Question
The total revenue in rupees received from the sale of x units of a product is given by R(x) = 3x2 + 36x + 5. The marginal revenue, when x = 15 is ______.
Options
116
96
90
126
Solution
The total revenue in rupees received from the sale of x units of a product is given by R(x) = 3x2 + 36x + 5. The marginal revenue, when x = 15 is 126.
Explanation:
We have R (x) = 3x2 + 36x + 5
Differentiate w.r.t. x, we get
`(dR)/ dx = d/dx (3x^2 + 36x + 5) = 6x + 36`
`∴ ((dR)/dx)_(x = 15)`
`= 6 xx 15 + 36`
= 126
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