The value of lim x → 0 x Sin(15/a) is?

Zero

Infinity

None of these

Since $lim_{x to 0} x sin(15/a)$ is of the form $x cdot text{constant}$ , and $x to 0$ , the whole expression tends to 0.

The sine function remains bounded, so multiplying by $x$ (which approaches zero) results in zero.