$5n-2=13$

$2x^2+4x-2x^2-5x+2abc-3abc$

$\int\frac{sen^2\left(x\right)}{1+cos\left(x\right)}dx$

$1\cdot2\cdot3\cdot4\cdot5\cdot6\cdot7\cdot8\cdot9\cdot10\cdot11\cdot12\cdot13\cdot14\cdot15\cdot16\cdot17\cdot18\cdot19\cdot20\cdot21\cdot22\cdot23\cdot24\cdot25\cdot26\cdot27\cdot28\cdot29\cdot30$

$\frac{p}{4}+7=12$

$2\sec\left(x\right)-\tan\left(x\right)$

$3x^3\:3$