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A(1)(x(1),y(1)),A(2)(x(2),y(2)),A(3)(x(3...

`A_(1)(x_(1),y_(1)),A_(2)(x_(2),y_(2)),A_(3)(x_(3),y_(3))`……….are a point in a plane such that
If `x_(1),y_(1)=2` and `x_(i)` 's form a G.P. with common ratio 2 and `y_(i)` 's form a G.P. with common ratio 3, then find the co ordinates of G.

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To find the coordinates of the centroid \( G \) of the points \( A_1(x_1, y_1), A_2(x_2, y_2), A_3(x_3, y_3), \ldots \) given the conditions in the problem, we will follow these steps: ### Step 1: Determine the coordinates of the points based on the given conditions. We know that: - \( A_1(x_1, y_1) = (2, 2) \) - The \( x_i \) coordinates form a geometric progression (G.P.) with a common ratio of 2. - The \( y_i \) coordinates form a geometric progression (G.P.) with a common ratio of 3. Using the formula for the \( n \)-th term of a G.P., we can express the coordinates as follows: For \( x_i \): - \( x_1 = 2 \) - \( x_2 = 2 \cdot 2 = 4 \) - \( x_3 = 2 \cdot 2^2 = 8 \) - In general, \( x_n = 2 \cdot 2^{n-1} = 2^n \) For \( y_i \): - \( y_1 = 2 \) - \( y_2 = 2 \cdot 3 = 6 \) - \( y_3 = 2 \cdot 3^2 = 18 \) - In general, \( y_n = 2 \cdot 3^{n-1} \) ### Step 2: Find the coordinates of the centroid \( G \). The coordinates of the centroid \( G \) of \( n \) points \( (x_1, y_1), (x_2, y_2), \ldots, (x_n, y_n) \) are given by: \[ G\left( \frac{x_1 + x_2 + \ldots + x_n}{n}, \frac{y_1 + y_2 + \ldots + y_n}{n} \right) \] #### Calculate \( x_1 + x_2 + \ldots + x_n \): \[ x_1 + x_2 + \ldots + x_n = 2 + 4 + 8 + \ldots + 2^n \] This is a geometric series with: - First term \( a = 2 \) - Common ratio \( r = 2 \) - Number of terms \( n \) The sum of the first \( n \) terms of a G.P. is given by: \[ S_n = a \frac{r^n - 1}{r - 1} = 2 \frac{2^n - 1}{2 - 1} = 2(2^n - 1) = 2^{n+1} - 2 \] Thus, \[ x_1 + x_2 + \ldots + x_n = 2^{n+1} - 2 \] #### Calculate \( y_1 + y_2 + \ldots + y_n \): \[ y_1 + y_2 + \ldots + y_n = 2 + 6 + 18 + \ldots + 2 \cdot 3^{n-1} \] This is also a geometric series with: - First term \( a = 2 \) - Common ratio \( r = 3 \) - Number of terms \( n \) The sum of the first \( n \) terms is: \[ S_n = a \frac{r^n - 1}{r - 1} = 2 \frac{3^n - 1}{3 - 1} = 2 \frac{3^n - 1}{2} = 3^n - 1 \] Thus, \[ y_1 + y_2 + \ldots + y_n = 3^n - 1 \] ### Step 3: Substitute into the centroid formula. Now substituting back into the centroid formula: \[ G\left( \frac{2^{n+1} - 2}{n}, \frac{3^n - 1}{n} \right) \] ### Final Answer: The coordinates of the centroid \( G \) are: \[ G\left( \frac{2^{n+1} - 2}{n}, \frac{3^n - 1}{n} \right) \]
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