$$a^2-5a^2$$

$$0,05\:x\:0,005$$

$$8\cos\left(v\right)^2-6\cos\left(v\right)+1=0$$

$$\left(5r\:+\:7f\right)\:\left(7f\:-\:5r\right)\:$$

$$\int\frac{e^x}{\left(e^{4x}-e^{2x}\right)}dx$$

$$4x^2-64^4cm^2$$

$$\left(-2xyz\right)\left(3x^2yz^3\right)\left(5x^2yz^4\right)$$