3x^2+7sqrt(5x)-30=0

解答

3 x^{2} + 7 5 x - 30 = 0

x \approx 1.75646 \dots

求解步骤

3 x^{2} + 7 5 x - 30 = 0

去除平方根

245 x = 9 x^{4} - 180 x^{2} + 900

解

245 x = 9 x^{4} - 180 x^{2} + 900 : x \approx 4.60379 \dots, x \approx 1.75646 \dots

x \approx 4.60379 \dots, x \approx 1.75646 \dots

验证解:

x \approx 4.60379 \dots

假

, x \approx 1.75646 \dots

真

解是

x \approx 1.75646 \dots

18 x - 8 - 2 x - 4 - 2 2 x + 1 = 0

so l v e f or a, 9 a + b \cdot b = 32

2 x + 5 + 10 x - 4 = 7

x^{3} + 3 x^{2} + 3 x - (x - 6)^{\frac{1}{3}} + 8 = 0

\frac{x}{( x - 5 )} + \frac{( x - 5 )}{x} = \frac{21}{6}