Square root of x^2-5x+4 is defined for x = ?

Expert Answers

An illustration of the letter 'A' in a speech bubbles

The square root of x^2 - 5x + 4 is a real value if x^2 - 5x + 4 >=0

x^2 - 5x + 4 = 0

=> x^2 - 4x - x + 4 =0

=> x(x - 4) - 1(x - 4) = 0

=> (x - 1)(x - 4) = 0

The roots are x = 1 and x = 4

For values of x such that 1< x < 4, x^2 - 5x + 4 < 0

Therefore the square root is defined when

x <= 1 and x >= 4.

Approved by eNotes Editorial Team

Posted on

Soaring plane image

We’ll help your grades soar

Start your 48-hour free trial and unlock all the summaries, Q&A, and analyses you need to get better grades now.

  • 30,000+ book summaries
  • 20% study tools discount
  • Ad-free content
  • PDF downloads
  • 300,000+ answers
  • 5-star customer support
Start your 48-Hour Free Trial