11a^2-7a-21=-6

解答

11 a^{2} - 7 a - 21 = - 6

a = \frac{7 + 709}{22}, a = \frac{7 - 709}{22}

十进制

a = 1.52850 \dots, a = - 0.89213 \dots

求解步骤

11 a^{2} - 7 a - 21 = - 6

将

6

para o lado esquerdo

11 a^{2} - 7 a - 15 = 0

使用求根公式求解

a_{1, 2} = \frac{- ( - 7 ) \pm ( - 7 ) ^{2} - 4 \cdot 11 ( - 15 )}{2 \cdot 11}

(- 7)^{2} - 4 \cdot 11 (- 15) = 709

a_{1, 2} = \frac{- ( - 7 ) \pm 709}{2 \cdot 11}

将解分隔开

a_{1} = \frac{- ( - 7 ) + 709}{2 \cdot 11}, a_{2} = \frac{- ( - 7 ) - 709}{2 \cdot 11}

a = \frac{- ( - 7 ) + 709}{2 \cdot 11} : \frac{7 + 709}{22}

a = \frac{- ( - 7 ) - 709}{2 \cdot 11} : \frac{7 - 709}{22}

二次方程组的解是:

a = \frac{7 + 709}{22}, a = \frac{7 - 709}{22}

s im pl i f y 1242 - 74512

\frac{6 x + 2}{x - 1} = 3

\frac{3}{8} x + 2 - \frac{4}{5} x = 1 + \frac{3}{10} x + \frac{3}{2}

s im pl i f y \frac{5 !}{( 5 - 3 ) !}

f a c t or 4 x^{3} - 6 x^{2} + 2 x