1,8,35,156,___
(x+1)/3 + 2x/4 = 47 - 2x
4*25
5*5
6+6+6+6*0=
inegral of ((1/x) -1/(x^0.99))
2*7
(0.7 × [65]) + (0.3 × [83])
express (100km,225 degrees) in the form (a,b)