a: \(\dfrac{2025}{2024}+\dfrac{2022}{2023}+\dfrac{1}{2023\times2024}\)
\(=1+\dfrac{1}{2024}+1-\dfrac{1}{2023}+\dfrac{1}{2023}-\dfrac{1}{2024}\)
=2
b: \(\dfrac{15\times14-1}{13\times15+14}\)
\(=\dfrac{14\times\left(14+1\right)-1}{14+\left(14-1\right)\left(14+1\right)}\)
\(=\dfrac{14^2+13}{14^2+13}=1\)
c: \(\dfrac{17}{2}-\dfrac{3}{4}-\dfrac{1}{2}-\dfrac{1}{4}\)
\(=\left(\dfrac{17}{2}-\dfrac{1}{2}\right)-\left(\dfrac{3}{4}+\dfrac{1}{4}\right)\)
\(=\dfrac{16}{2}-1=8-1=7\)
d: \(13\times\dfrac{7}{2}+\dfrac{7}{2}\times6+\dfrac{7}{2}\)
\(=\dfrac{7}{2}\times\left(13+6+1\right)\)
\(=\dfrac{7}{2}\times20=70\)