# Shrink the numerator

Calculus Level 4

$\large f(x) = \frac{ A \sin(x) + B \sin(2x) + \sin(3x) }{x^5}$

For $$x \ne 0$$, let $$f(x)$$ be expressed as above for constants $$A,B$$.

If $$f(x)$$ is continuous at $$x=0$$, find $$A+B$$.

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