Unravel the Equation: Solving √(x+1) × √(x+2) = x+3

Question

Solve the following equation:

x+1×x+2=x+3 \sqrt{x+1}\times\sqrt{x+2}=x+3

Video Solution

Solution Steps

00:00 Find X
00:03 Square both sides to eliminate the radicals
00:13 Expand brackets correctly, multiply each term by each term
00:30 Use the shortened multiplication formulas to expand the brackets
00:41 Collect like terms
00:51 Simplify where possible
00:55 Isolate X
01:10 And this is the solution to the problem

Step-by-Step Solution

To solve the equation x+1×x+2=x+3 \sqrt{x+1} \times \sqrt{x+2} = x+3 , we will follow these steps:

  • Step 1: Identify the terms. Let a=x+1 a = \sqrt{x+1} and b=x+2 b = \sqrt{x+2} , so ab=x+3 a \cdot b = x + 3 .
  • Step 2: Square both sides of the equation to remove the square roots: (ab)2=(x+3)2 (ab)^2 = (x+3)^2 .
  • Step 3: Express using the original variables: (x+1)(x+2)=(x+3)2 (x+1)(x+2) = (x+3)^2 .
  • Step 4: Expand both sides:
    Left side: x2+3x+2 x^2 + 3x + 2
    Right side: x2+6x+9 x^2 + 6x + 9 .
  • Step 5: Rearrange and simplify the equation by subtracting one side from the other:
    x2+3x+2=x2+6x+9 x^2 + 3x + 2 = x^2 + 6x + 9 becomes 0=3x+7 0 = 3x + 7 .
  • Step 6: Solve the linear equation: 3x=7 3x = -7 , hence x=73 x = -\frac{7}{3} .
  • Step 7: Verify that the solution x=73 x = -\frac{7}{3} fits the initial domain requirements for the square roots.

Therefore, the solution to the problem is x=73 x = -\frac{7}{3} . This matches choice 3 in the provided answer choices.

Answer

x=73 x=-\frac{7}{3}