Question

Дано 7, -11

Найти q, b3, b6, s5


И дано -3, 12

Answer 1

$b_1=7; ,; b_2=-11; ,...; ; to \\q=frac{b_1}{b_1}=-frac{11}{7}\\b_3=b_2cdot q=-11cdot frac{-11}{7}=frac{121}{7}\\b_6=b_1q^5=7cdot (-frac{11}{7})^5=7cdot (-frac{11^5}{7^5})=-frac{11^5}{7^4}=-frac{161051}{2401}=67frac{184}{2401}\\S_5=frac{b_1, (q^5-1)}{q-1}=frac{7cdot (-frac{11^5}{7^5}-1)}{-frac{11}{7}-1}=frac{7cdot frac{-161051-16807}{7^5}}{-frac{18}{7}}=frac{-1777858}{-18cdot 7^3}=287frac{5920}{6174}$