Animated Solution for Mathematics - Quadratic Equations: If α and β(α<β) are the roots of the equation (−2+3)(∣x−3∣)+(x−6x)+(9−23)=0,x≥0, then αβ+αβ is equal to :
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Visualized Solution
Analyzing the Given Equation
Given: (−2+3)∣x−3∣+(x−6x)+(9−23)=0
Condition: x≥0
We need to find the roots α and β.
First Substitution: t=x
Let t=x.
Since x≥0, we must have t≥0.
The term (x−6x) becomes (t2−6t).
Rearranging the Equation
Substitute t into the original equation:
(−2+3)∣t−3∣+(t2−6t)+(9−23)=0
Group the terms smartly:
(t2−6t+9)+(−2+3)∣t−3∣−23=0
Forming the Perfect Square
Recognize the perfect square: t2−6t+9=(t−3)2
Recall the absolute value property: y2=∣y∣2
Therefore, (t−3)2=∣t−3∣2
Transforming to a Quadratic in Modulus
The equation becomes:
∣t−3∣2+(3−2)∣t−3∣−23=0
Let u=∣t−3∣.
Constraint: Since it's an absolute value, u≥0.
The New Quadratic Equation
Substitute u:
u2+(3−2)u−23=0
Expand the middle term to factorize:
u2+3u−2u−23=0
Factorizing the Quadratic
Group the terms:
u(u+3)−2(u+3)=0
Take out the common factor (u+3):
(u−2)(u+3)=0
Solving for u and Applying Constraints
From the factors, we get two possible values:
u=2 or u=−3
Recall our constraint: u≥0
Therefore, u=−3 is rejected.
We accept u=2.
Back-Substituting to Find t
Substitute u=∣t−3∣ back:
∣t−3∣=2
This gives two cases:
Case 1: t−3=2⟹t=5
Case 2: t−3=−2⟹t=1
Finding the Roots x
Recall our first substitution: t=x⟹x=t2
For t=1: x=12=1
For t=5: x=52=25
The roots of the equation are 1 and 25.
Identifying α and β
The problem states the roots are α and β with α<β.
Comparing our roots 1 and 25:
α=1
β=25
Setting Up the Final Expression
We need to evaluate: αβ+αβ
Substitute α=1 and β=25:
125+1⋅25
Final Calculation
Simplify the terms:
25+25
5+5=10
Final Answer: 10
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The Sigma Insight: Transformation of Equations
Solution Diagram
Analyzing the Setup
Imagine you are standing before a complex, intimidating equation:
(−2+3)∣x−3∣+(x−6x)+(9−23)=0
At first glance, it looks like a chaotic mess of square roots and absolute values. But in the world of JEE Advanced, chaos is often just order in disguise. Our goal today is to peel back the layers of this expression to reveal the elegant quadratic structure hiding beneath.
The Art of Substitution
Whenever you see x appearing repeatedly, your first instinct should be to simplify the landscape. Let us define a new variable, t=x.
Since x≥0, we know that t must be non-negative (t≥0). Our equation now transforms into:
(−2+3)∣t−3∣+(t2−6t)+(9−23)=0
Look closely at the terms (t2−6t+9). This is the expansion of (t−3)2. We have a perfect square sitting right there, waiting to be recognized.
The Power of the Modulus
We know that for any real number y, y2=∣y∣2. Therefore, we can rewrite (t−3)2 as ∣t−3∣2.
Now, watch how the equation cleans up when we group the terms:
∣t−3∣2+(3−2)∣t−3∣−23=0
By letting u=∣t−3∣, we have successfully reduced a terrifying radical equation into a simple, beautiful quadratic:
u2+(3−2)u−23=0
Solving the Quadratic
Now, we factorize. We need two numbers that multiply to −23 and add to 3−2. Those numbers are 3 and −2.
Thus, the equation becomes:
(u−2)(u+3)=0
This gives us two potential paths: u=2 or u=−3. However, we must remember our constraint: u=∣t−3∣, which must be ≥0.
We must reject u=−3 because an absolute value cannot be negative. We are left with the only valid solution: u=2.
The Final Reveal
Now we backtrack. Since u=∣t−3∣=2, we have two cases for t:
1. t−3=2⟹t=5
2. t−3=−2⟹t=1
Since t=x, we square these values to find x: x=25 and x=1. Given the condition α<β, we identify α=1 and β=25.
Finally, we calculate the expression αβ+αβ:
125+1⋅25=25+25=5+5=10
And there it is—the final answer is 10. What started as a daunting expression collapsed into a simple, elegant result.