Cambridge International AS Level · Mathematics - Further (9231)

多項式方程的根:练习题

5 道选择题即时批改,另有 5 道文字题附完整解题步骤,全部围绕「多項式方程的根」。

10 道题目24 免费,无需注册
第 1 题
1

The roots of the cubic equation \(x^3 - 5x^2 + 7x - 3 = 0\) are \(\alpha\), \(\beta\), and \(\gamma\). Find the value of \(\alpha + \beta + \gamma\).

第 2 题
1

The equation \(x^4 + 2x^2 + 4x + 1 = 0\) has roots \(\alpha, \beta, \gamma, \delta\). Using the substitution \(y = x^2\), find a quartic equation in \(y\) whose roots are \(\alpha^2, \beta^2, \gamma^2, \delta^2\). Hence, find the value of \(\sum \alpha^4\).

第 3 题
1

The equation \(x^4 + ax^3 + bx^2 + cx + d = 0\) has roots \(\alpha, \beta, \gamma, \delta\). It is given that \(\sum \alpha = 2\), \(\sum \alpha\beta = -1\), \(\sum \alpha\beta\gamma = -4\), and \(\alpha\beta\gamma\delta = 1\). Find the value of \(\frac{1}{\alpha^2} + \frac{1}{\beta^2} + \frac{1}{\gamma^2} + \frac{1}{\delta^2}\).

第 4 题
1

The roots of the cubic equation \(x^3 - 3x^2 + 4x - 6 = 0\) are \(\alpha\), \(\beta\), and \(\gamma\).
Find the value of \(\alpha^2 + \beta^2 + \gamma^2\).

第 5 题
1

Given that \(\alpha\), \(\beta\), and \(\gamma\) are the roots of the cubic equation \(x^3 + px^2 + qx + r = 0\), find the value of \(\alpha^2 + \beta^2 + \gamma^2\) in terms of the coefficients.

第 6 题
2

The roots of the quartic equation \(2x^4 - 8x^3 + 5x^2 - x + 6 = 0\) are \(p\), \(q\), \(r\), and \(s\). Find the value of \(\frac{1}{p} + \frac{1}{q} + \frac{1}{r} + \frac{1}{s}\).

先自己写一遍答案,再对照解题步骤。

第 7 题
3

The roots of the cubic equation \(x^3 + 3x - 2 = 0\) are \(\alpha\), \(\beta\), and \(\gamma\). Use the substitution \(u = x + 2\) to find a cubic equation in \(u\) whose roots are \(\alpha + 2\), \(\beta + 2\), and \(\gamma + 2\).

先自己写一遍答案,再对照解题步骤。

第 8 题
5

The quartic equation \(x^4 - 3x^3 + 2x^2 - x + 5 = 0\) has roots \(\alpha, \beta, \gamma, \delta\). Find the value of \(\sum \alpha^2 \beta^2\).

先自己写一遍答案,再对照解题步骤。

第 9 题
4

The quadratic equation \( x^2 + px + q = 0 \) has roots \( \alpha \) and \( \beta \). Given that \( \alpha + \beta = 7 \) and \( \alpha^2 + \beta^2 = 25 \), find the values of the constants p and q.

先自己写一遍答案,再对照解题步骤。

第 10 题
5

Given that the roots of \( x^3 - 6x^2 + kx - 8 = 0 \) are in geometric progression, find:
(a) the value of the constant k,
(b) the three roots of the equation.

先自己写一遍答案,再对照解题步骤。

* thinka 提供的内容由 AI 生成,未必在任何情况下都完全准确或最新,请结合官方教材与教师指导使用。

你已看过标准答案。现在轮到你的答案被批改。

这一页能告诉你好答案是什么样子,却无法指出你的答案缺了什么。thinka 按真实评分标准批改你的文字答案,约 15 秒完成。

想多做几道同类题目?立即开始练习这个课题,边做边批改。

立即练习