﻿ The length of a longest interval in which the function 3 sin x – 4Sin3x is increasing is : Kaysons Education

# The Length Of A Longest Interval In Which The Function 3 Sin x – 4Sin3x is Increasing Is

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## Question

### Solution

Correct option is

π/3

Since 3 sin x – 4 sin3x = sin 3x and sin 3x increases when 3x takes values from –π/2 to π/2 or x takes value from π/6 to π/6. Thus, the length of the longest interval in which 3 sinx – 4 sin3x increases is π/6 – (π/6) = π/3.

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