Current location - Training Enrollment Network - Mathematics courses - Speaking of difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult math problems.
Speaking of difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult, difficult math problems.
This is an arithmetic series. If you haven't learned it, ask for 6+8+ 10+. . . . +26+28+30 (and then refer to Gaussian algorithm, the first term+the last term) is 6+30=8+28= 10+26=. . =36 A * * * There are 6 pairs, plus 18, it is 234.