If for θ∈[−π3,0]\theta \in \left[ -\frac{\pi}{3}, 0 \right], the points (x,y)=(3tan⁡(θ+π3),2tan⁡(θ+π6))(x, y) = \left( 3 \tan\left(\theta + \frac{\pi}{3}\right), 2 \tan\left(\theta + \frac{\pi}{6}\right) \right) lie on xy+αx+βy+γ=0xy + \alpha x + \beta y + \gamma = 0, then α2+β2+γ2\alpha^2 + \beta^2 + \gamma^2 is equal to:

Answer: 337

Step-by-step solution

Step 1: Define x and y in terms of new variables

Let's simplify the expressions for xx and yy by introducing new variables. We define A=θ+π3A = \theta + \frac{\pi}{3} and B=θ+π6B = \theta + \frac{\pi}{6}. This makes the expressions for xx and yy more manageable.

Step 2: Find the relationship between A and B

Now, let's find the relationship between AA and BB. Subtracting BB from AA, we get (θ+π3)−(θ+π6)=π3−π6=2π−π6=π6(\theta + \frac{\pi}{3}) - (\theta + \frac{\pi}{6}) = \frac{\pi}{3} - \frac{\pi}{6} = \frac{2\pi - \pi}{6} = \frac{\pi}{6}. This constant difference will be useful.

Step 3: Apply the tangent subtraction formula

We know the value of A−BA - B, so we can use the tangent subtraction formula. The formula states that tan⁡(A−B)\tan(A - B) is equal to (tan⁡A−tan⁡B)(\tan A - \tan B) divided by (1+tan⁡Atan⁡B)(1 + \tan A \tan B).

Step 4: Substitute and rearrange the equation

Substitute tan⁡(A−B)=tan⁡(π6)=13\tan(A - B) = \tan(\frac{\pi}{6}) = \frac{1}{\sqrt{3}}, tan⁡A=x3\tan A = \frac{x}{3}, and tan⁡B=y2\tan B = \frac{y}{2} into the tangent formula. After cross-multiplication and rearrangement, we get xy−2x+3y−18=0xy - 2x + 3y - 18 = 0. This is the equation of the locus.

Step 5: Compare with the given equation to find alpha, beta, gamma

The given equation is xy+αx+βy+γ=0xy + \alpha x + \beta y + \gamma = 0. By comparing this with our derived equation xy−2x+3y−18=0xy - 2x + 3y - 18 = 0, we can identify the values of α\alpha, β\beta, and γ\gamma.

Step 6: Calculate the final expression

Finally, we need to calculate α2+β2+γ2\alpha^2 + \beta^2 + \gamma^2. Substitute the values we found: (−2)2+(3)2+(−18)2=4+9+324=337(-2)^2 + (3)^2 + (-18)^2 = 4 + 9 + 324 = 337.

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