Answer:
x ≈ 0.1459
Explanation:
Since you only want a small positive solution, you can use the arcsine function to find it.
6sin(5x) = 4
sin(5x) = 4/6 = 2/3
5x = arcsin(2/3)
x = arcsin(2/3)/5
x ≈ 0.1459
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A graphing calculator can find the solution easily. It is often easiest to rewrite the equation so you're looking for a solution that makes the value zero. Here, subtracting 4 from both sides does that.