Question

10.15. Упростите выражение (а⁵b³)⁶•(a⁷b⁴)⁵:(a²¹b¹²)³ и найдите его значения при а= - 5/11 и b=3 2/3​

Answer 1

$(a^{5}b^{3})^{6}\cdot(a^{7} b^{4})^{5}:(a^{21}b^{12})^{3} =a^{30}b^{18} \cdot a^{35}b^{20}:a^{63}b^{36}=\\\\=a^{30+35-63} \cdot b^{18+20-36}=a^{2} b^{2}\\\\a=-\dfrac{5}{11} \ ; \ b=3\dfrac{2}{3}\\\\\\a^{2}b^{2} =\Big(-\dfrac{5}{11}\Big)^{2} \cdot \Big(3\dfrac{2}{3}\Big)^{2} =\dfrac{25}{121} \cdot \Big(\dfrac{11}{3}\Big)^{2} =\dfrac{25}{121} \cdot\dfrac{121}{9} =\dfrac{25}{9} =\boxed{2\dfrac{7}{9}}$