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If the locus of the point which moves so...

If the locus of the point which moves so that the difference (p) 0 of its distance from the points `(5, 0) and (-5,0)` is 2 is `x^2/a^2-y^2/24=1` then a is

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To solve the problem step by step, we will find the value of \( a \) given the locus of the point \( P(h, k) \) such that the difference of its distances from the points \( (5, 0) \) and \( (-5, 0) \) is 2. ### Step 1: Define the distances Let \( P(h, k) \) be the point whose locus we are trying to find. The distance from \( P(h, k) \) to \( (5, 0) \) is given by: \[ d_1 = \sqrt{(h - 5)^2 + k^2} \] The distance from \( P(h, k) \) to \( (-5, 0) \) is given by: \[ d_2 = \sqrt{(h + 5)^2 + k^2} \] ### Step 2: Set up the equation According to the problem, the difference of these distances is 2: \[ d_1 - d_2 = 2 \] Substituting the distances we found: \[ \sqrt{(h - 5)^2 + k^2} - \sqrt{(h + 5)^2 + k^2} = 2 \] ### Step 3: Isolate one of the square roots Rearranging the equation gives: \[ \sqrt{(h - 5)^2 + k^2} = 2 + \sqrt{(h + 5)^2 + k^2} \] ### Step 4: Square both sides Now, we square both sides to eliminate the square root: \[ (h - 5)^2 + k^2 = (2 + \sqrt{(h + 5)^2 + k^2})^2 \] Expanding the right side: \[ (h - 5)^2 + k^2 = 4 + 4\sqrt{(h + 5)^2 + k^2} + (h + 5)^2 + k^2 \] ### Step 5: Simplify the equation By simplifying, we can cancel \( k^2 \) from both sides: \[ (h - 5)^2 = 4 + 4\sqrt{(h + 5)^2 + k^2} + (h + 5)^2 \] ### Step 6: Rearranging and isolating the square root Rearranging gives: \[ (h - 5)^2 - (h + 5)^2 = 4 + 4\sqrt{(h + 5)^2 + k^2} \] Using the difference of squares: \[ [(h - 5) - (h + 5)][(h - 5) + (h + 5)] = 4 + 4\sqrt{(h + 5)^2 + k^2} \] This simplifies to: \[ -10 \cdot 2h = 4 + 4\sqrt{(h + 5)^2 + k^2} \] Thus: \[ -20h = 4 + 4\sqrt{(h + 5)^2 + k^2} \] ### Step 7: Isolate the square root again Rearranging gives: \[ -20h - 4 = 4\sqrt{(h + 5)^2 + k^2} \] Dividing by 4: \[ -5h - 1 = \sqrt{(h + 5)^2 + k^2} \] ### Step 8: Square both sides again Squaring both sides again: \[ (-5h - 1)^2 = (h + 5)^2 + k^2 \] Expanding both sides: \[ 25h^2 + 10h + 1 = h^2 + 10h + 25 + k^2 \] ### Step 9: Rearranging terms Bringing all terms to one side: \[ 25h^2 - h^2 + 1 - 25 = k^2 \] This simplifies to: \[ 24h^2 - 24 = k^2 \] Dividing by 24: \[ \frac{h^2}{1} - \frac{k^2}{24} = 1 \] ### Step 10: Identify the value of \( a \) From the equation \( \frac{x^2}{a^2} - \frac{y^2}{24} = 1 \), we can see that \( a^2 = 1 \), hence: \[ a = \pm 1 \] ### Final Answer Thus, the value of \( a \) is \( 1 \). ---
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