1: Tính hợp lí:
a, \(\dfrac{11}{125}\)- \(\dfrac{17}{18}-\dfrac{5}{7}+\dfrac{4}{9}\)+ \(\dfrac{17}{14}\)
b,\(-1\dfrac{5}{7}.15+\dfrac{2}{7}.\left(-15\right)+\left(-105\right).\left(\dfrac{2}{3}-\dfrac{4}{5}+\dfrac{1}{7}\right)\)
2: Tìm x:
a, \(\dfrac{11}{13}-\left(\dfrac{5}{42}-x\right)=-\left(\dfrac{15}{28}-\dfrac{11}{13}\right)\)
b,\(|x+\dfrac{4}{15}|-|-3,75|=-|-2,15|\)
c, \(^{7^{x+2}}+2.7^{x-1}=345\)