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The number of real roots of the equation x   ∣ x − 2 ∣ + 3 ∣ x − 3 ∣ + 1 = 0 is:

The number of real roots of the equation x   ∣ x − 2 ∣ + 3 ∣ x − 3 ∣ + 1 = 0 is:

Question:

The number of real roots of the equation

x ∣x−2∣+3∣x−3∣+1=0 is:

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The number of real roots of the equation  x   ∣ x − 2 ∣ + 3 ∣ x − 3 ∣ + 1 = 0 is:


Short Solution (Text):

Critical points for the absolute values are x=2x=2 and x=3x=3. Solve piecewise in the three intervals.

1) Region x<2x<2:
∣x−2∣=2−x,  ∣x−3∣=3−x|x-2|=2-x,\; |x-3|=3-x. The equation becomes

x(2−x)+3(3−x)+1=0⇒−x2−x+10=0⇒x2+x−10=0.x(2-x) + 3(3-x) + 1 = 0 \\ \Rightarrow -x^2 - x + 10 = 0 \\ \Rightarrow x^2 + x - 10 = 0.

Discriminant Δ=1+40=41\Delta = 1 + 40 = 41. Roots:

x=−1±412.x = \frac{-1 \pm \sqrt{41}}{2}.

Numeric values: −1+412≈2.7016\dfrac{-1+\sqrt{41}}{2}\approx 2.7016 and −1−412≈−3.7016\dfrac{-1-\sqrt{41}}{2}\approx -3.7016.
Only x≈−3.7016x\approx -3.7016 lies in this region (x<2x<2) → one valid root here.

2) Region 2≤x<32 \le x < 3:
∣x−2∣=x−2,  ∣x−3∣=3−x|x-2|=x-2,\; |x-3|=3-x. The equation becomes

x(x−2)+3(3−x)+1=0⇒x2−5x+10=0.x(x-2) + 3(3-x) + 1 = 0 \\ \Rightarrow x^2 - 5x + 10 = 0.

Discriminant Δ=25−40=−15<0\Delta = 25 - 40 = -15 <0 → no real roots in this interval.

3) Region x≥3x\ge 3:
∣x−2∣=x−2,  ∣x−3∣=x−3|x-2|=x-2,\; |x-3|=x-3. The equation becomes

x(x−2)+3(x−3)+1=0⇒x2+x−8=0.x(x-2) + 3(x-3) + 1 = 0 \\ \Rightarrow x^2 + x - 8 = 0.

Discriminant Δ=1+32=33\Delta = 1 + 32 = 33. Roots:

x=−1±332≈2.3723,  −3.3723.x = \frac{-1 \pm \sqrt{33}}{2}\approx 2.3723,\; -3.3723.

Neither root satisfies x≥3x\ge 3 → no valid roots here.


✅ Final Answer:
Number of real roots = 1
(the only real solution is x=−1−412≈−3.7016x = \dfrac{-1-\sqrt{41}}{2}\approx -3.7016).

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