Let \( a \) be a real number such that the function \( f(x)=a x^{2}+6 x-15, x \in R \) is increasing in \( \left(-\infty…

Let \( a \) be a real number such that the function \( f(x)=a x^{2}+6 x-15, x \in R \) is increasing in \( \left(-\infty, \frac{3}{4}\right) \) and decreasing in \( \left(\frac{3}{4}, \infty\right) \). Then the function \( g(x)=a x^{2}-6 x+15, x \in R \) has a:

[JEE Main 2021, 20 Jul (Shift 1)]