Hill Long
05/27/2024 · Primary School

If \( x^{2}-7 x+1=0 \), what is \( x+\frac{1}{x}-7 ? \)

UpStudy ThothAI Solution

Tutor-Verified Answer

Step-by-step Solution

Given the equation \( x^{2}-7x+1=0 \), we need to find the value of \( x+\frac{1}{x}-7 \). To find the value of \( x+\frac{1}{x}-7 \), we first need to solve the equation \( x^{2}-7x+1=0 \) to find the values of \( x \). Let's solve the equation \( x^{2}-7x+1=0 \) using the quadratic formula. Solve the quadratic equation by following steps: - step0: Solve using the quadratic formula: \(x^{2}-7x+1=0\) - step1: Solve using the quadratic formula: \(x=\frac{7\pm \sqrt{\left(-7\right)^{2}-4}}{2}\) - step2: Simplify the expression: \(x=\frac{7\pm \sqrt{45}}{2}\) - step3: Simplify the expression: \(x=\frac{7\pm 3\sqrt{5}}{2}\) - step4: Separate into possible cases: \(\begin{align}&x=\frac{7+3\sqrt{5}}{2}\\&x=\frac{7-3\sqrt{5}}{2}\end{align}\) - step5: Rewrite: \(x_{1}=\frac{7-3\sqrt{5}}{2},x_{2}=\frac{7+3\sqrt{5}}{2}\) The solutions to the equation \( x^{2}-7x+1=0 \) are \( x_{1}=\frac{7-3\sqrt{5}}{2} \) and \( x_{2}=\frac{7+3\sqrt{5}}{2} \). Now, we can substitute these values of \( x \) into the expression \( x+\frac{1}{x}-7 \) to find the value. Let's calculate it. Calculate the value by following steps: - step0: Calculate: \(\frac{7-3\sqrt{5}}{2}+\frac{2}{7-3\sqrt{5}}-7\) - step1: Reduce fractions to a common denominator: \(\frac{\left(7-3\sqrt{5}\right)\left(7-3\sqrt{5}\right)}{2\left(7-3\sqrt{5}\right)}+\frac{2\times 2}{\left(7-3\sqrt{5}\right)\times 2}-\frac{7\left(14-6\sqrt{5}\right)}{14-6\sqrt{5}}\) - step2: Calculate: \(\frac{94-42\sqrt{5}}{14-6\sqrt{5}}+\frac{4}{14-6\sqrt{5}}-\frac{98-42\sqrt{5}}{14-6\sqrt{5}}\) - step3: Transform the expression: \(\frac{94-42\sqrt{5}+4-\left(98-42\sqrt{5}\right)}{14-6\sqrt{5}}\) - step4: Remove the parentheses: \(\frac{94-42\sqrt{5}+4-98+42\sqrt{5}}{14-6\sqrt{5}}\) - step5: Calculate: \(\frac{0}{14-6\sqrt{5}}\) - step6: Calculate: \(0\) The value of \( x+\frac{1}{x}-7 \) is 0 when \( x=\frac{7-3\sqrt{5}}{2} \). Similarly, when \( x=\frac{7+3\sqrt{5}}{2} \), the value of \( x+\frac{1}{x}-7 \) is also 0. Therefore, the value of \( x+\frac{1}{x}-7 \) is 0 for both solutions of the equation \( x^{2}-7x+1=0 \).

Quick Answer

The value of \( x+\frac{1}{x}-7 \) is 0 for both solutions of the equation \( x^{2}-7x+1=0 \).
Answered by UpStudy AI and reviewed by a Professional Tutor
UpStudy ThothAI
Self-Developed and Ever-Improving
Thoth AI product is constantly being upgraded and optimized.
Covers All Major Subjects
Capable of handling homework in math, chemistry, biology, physics, and more.
Instant and Accurate
Provides immediate and precise solutions and guidance.
Try Now
Ask Tutors
Ask AI
10x
Fastest way to Get Answers & Solutions
By text

Enter your question here…

By image
Re-Upload
Uploaded Files
xxxx.png0%
Submit
📸 STUDY CAN BE A REAL STRUGGLE
Why Not UpStudy It?
Select your plan below
Premium

You can enjoy

  • Step-by-step explanations
  • 24/7 expert live tutors
  • Unlimited number of questions
  • No interruptions
  • Full access to answer and
    solution
Basic
  • Limited Solutions