Cho phương trình (x-2013)/16+(x-1997)/11+(x-1992)/9+(x-1991)/7=10
Giải thích
x−200316+x−199711+x−19929+x−19917=10⇔x−200316−1+x−199711−2+x−19929−3+x−19917−4=0
⇔x−201916+x−201911+x−20199+x−20197=0⇔x−2019116+111+19+17=0Do 116+111+19+17>0⇒x−2019=0⇔x=2019S=2019