$\frac{36x^4-109x^2+25}{3x-5}$

$\left(3^2\right)^2\cdot\left(2\cdot6^5\right)^{-2}\cdot\left(2^2\right)^3$

$-68\:-\:80$

$\left(15^4\right)^{-49}$

$\sin\left(2x\right)\cdot\cos\left(x\right)=0$

$\left(1-\cos\left(x\right)^2\right)^2$

$\sqrt{2}m-42b+2.6+-0.414213m+84b-5.8$