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प्रश्न
Solve the following equation and also verify your solution:
(x + 2)(x + 3) + (x − 3)(x − 2) − 2x(x + 1) = 0
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उत्तर १
\[(x + 2)(x + 3) + (x - 3)(x - 2) - 2x(x + 1) = 0\]
\[\text{ or }x^2 + 5x + 6 + x^2 - 5x + 6 - 2 x^2 - 2x = 0\]
\[\text{ or }12 - 2x = 0\]
\[\text{ or }x = \frac{12}{2} = 6\]
\[\text{ Verification: }\]
\[\text{ L . H . S . }= (6 + 2)(6 + 3) + (6 - 3)(6 - 2) - 2 \times 6(6 + 1)\]
\[ = 72 + 12 - 84 = 0 =\text{ R . H . S .}\]
उत्तर २
(x + 2)(x + 3) + (x − 3)(x − 2) − 2x(x + 1) = 0
⇒ [x2 + (2 + 3)x + 2 × 3] + [x2 + (-3 - 2)x + (-3)(-2)] - 2x2 - 2x ∴
⇒ x2 + 5x + 6 + x2 - 5x + 6 - 2x2 - 2x = 0
⇒ x2 + x2 - 2x2 + 5x - 5x - 2x + 6 + 6 = 0
= - 2x + 12 = 0
Substracting 12 from both sides
-2x + 12 - 12 = 0 - 12 ⇒ - 2x = -12
Dividing by -2
`"-2x"/-2 = (-12)/-2 => x = 6`
∴ x = 6
Verification:
L.H.S. = (x + 2)(x + 3) + (x - 3)(x - 2) - 2x (x + 1)
= (6 + 2)(6 + 3) + (6 - 3)(6 - 2) - 2 × 6(6 + 1)
= 8 × 9 + 3 × 4 - 12 × 7
= 72 + 12 - 84 = 84 - 84 = 0 = R.H.S.
