Đáp án:
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Giải thích các bước giải:
Đề sai hay sao đó bạn.
$\dfrac{8}{15}\times\dfrac{11}{17}+\dfrac{6}{17}\times\dfrac{8}{13}-1\dfrac8{15}\\=\dfrac{11}{15}\times\dfrac{8}{17}+\dfrac{8}{17}\times\dfrac{6}{13}-1\dfrac{8}{15}\\=\dfrac{8}{17}\times\left(\dfrac{11}{15}+\dfrac{6}{13}\right)-1\dfrac8{15}\\=\dfrac{8}{17}\times\dfrac{233}{195}-1\dfrac{8}{15}\\=\dfrac{1864}{3315}-\dfrac{23}{15}\\=\dfrac{-1073}{1105}$
Hoặc mình có thể mạnh dạn sửa đề.
$\dfrac{8}{15}\times\dfrac{11}{17}+\dfrac{6}{17}\times\dfrac{8}{15}-1\dfrac8{15}\\=\dfrac{8}{15}\times\left(\dfrac{11}{17}+\dfrac{6}{17}\right)-1\dfrac{8}{15}\\=\dfrac{8}{15}\times1-1\dfrac{8}{15}\\=\dfrac{8}{15}-1\dfrac{8}{15}\\=-1$
