Solve Complex Fraction Equation: Finding A, B, C in (A/x + Bx/2) = (2x-3)²/x - C

Question

Ax+Bx2=(2x3)2xc \frac{A}{x}+\frac{Bx}{2}=\frac{(2x-3)^2}{x}-c

Calculate the values of A, B, and C.

Video Solution

Solution Steps

00:00 Find A,B,C for which the equation holds
00:03 Multiply by common denominator to eliminate fractions
00:34 Arrange the equation
00:40 Use shortened multiplication formulas to expand brackets
00:58 Calculate the squares and products
01:12 Carefully expand brackets properly, multiply by each factor
01:22 Compare equal terms to find A,B,C
01:28 This is the solution for B
01:34 Continue with the same method to find C,A
01:43 This is the solution for C
01:51 And this is the solution for A
01:54 And this is the solution to the question

Step-by-Step Solution

To solve this problem, we'll proceed with the following steps:

  • Step 1: Expand the expression (2x3)2(2x-3)^2 on the right-hand side.
  • Step 2: Simplify the resulting expression by dividing by xx.
  • Step 3: Compare the terms on both sides of the equation to deduce the coefficients AA, BB, and CC.

Now, let us work through these steps:

Step 1: Expand the expression (2x3)2(2x-3)^2.

(2x3)2=4x212x+9 (2x - 3)^2 = 4x^2 - 12x + 9

Step 2: Substitute back into the equation and simplify by dividing by xx:

Ax+Bx2=4x212x+9xC \frac{A}{x} + \frac{Bx}{2} = \frac{4x^2 - 12x + 9}{x} - C

This simplifies to:

4x12+9xC 4x - 12 + \frac{9}{x} - C

Step 3: To find AA, BB, and CC, compare coefficients of similar terms:

  • Constant term (no xx): Equate 12-12 with C-C to get C=12C = 12 (note: should consider sign reversal).
  • Coefficient of xx: Compare B2\frac{B}{2} to 4. Giving B=8B = 8.
  • Coefficient of 1x\frac{1}{x}: Compare AA to 9, giving A=9A = 9.

Therefore, the solution to the problem is that the values are A = 9, B = 8, C = -12 \textbf{A = 9, B = 8, C = -12} .

Answer

A=9,B=8,C=12 A=9,B=8,C=-12