\(k,=\dfrac{2020x2019+2x2020-2045}{1945+2019x2020}=\dfrac{2020x2019-1945}{1945+2019x2020}=1\\ l,=\dfrac{637x526+637-189}{637x526+448}=\dfrac{637x256+448}{637x256+448}=1\\ m,=\dfrac{2017x2018+2017-1}{2017x2018+2016}=\dfrac{2017x2018+2016}{2017x2018+2016}=1\\ n,=\dfrac{15x13+15-1}{15x13+14}=\dfrac{15x13+14}{15x13+14}=1\)
tick mik nha
n: \(\dfrac{15\cdot14-1}{13\cdot15+14}=\dfrac{15\cdot14-1}{14^2-1+14}=\dfrac{15\cdot14-1}{14^2+13}=1\)
m: Ta có: \(\dfrac{2017\cdot2019-1}{2017\cdot2018+2016}\)
\(=\dfrac{2017\cdot\left(2018+1\right)-1}{2017\cdot2018+2016}\)
\(=\dfrac{2017\cdot2018+2017-1}{2017\cdot2018+2016}\)
=1
4 và 5
