Step 1: Understand the problem
We need to find the transformed equation of the given quadratic surface:
\[
2x^2 + 3y^2 - z^2 - 8x + 18y + 2z + 9 = 0
\]
after translating the coordinate axes to the point \((2, -3, 1)\).
Step 2: Translate the coordinates
Let the new coordinates after translation be:
\[
X = x - 2, \quad Y = y + 3, \quad Z = z - 1
\]
So, the original variables become:
\[
x = X + 2, \quad y = Y - 3, \quad z = Z + 1
\]
Step 3: Substitute into the original equation
Substitute \(x = X + 2\), \(y = Y - 3\), and \(z = Z + 1\) into the equation:
\[
2(X+2)^2 + 3(Y-3)^2 - (Z+1)^2 - 8(X+2) + 18(Y-3) + 2(Z+1) + 9 = 0
\]
Step 4: Expand each term
\[
2(X^2 + 4X + 4) + 3(Y^2 - 6Y + 9) - (Z^2 + 2Z + 1) - 8X - 16 + 18Y - 54 + 2Z + 2 + 9 = 0
\]
Simplify:
\[
2X^2 + 8X + 8 + 3Y^2 - 18Y + 27 - Z^2 - 2Z - 1 - 8X - 16 + 18Y - 54 + 2Z + 2 + 9 = 0
\]
Step 5: Combine like terms
- \(8X - 8X = 0\)
- \(-18Y + 18Y = 0\)
- \(-2Z + 2Z = 0\)
- Constants: \(8 + 27 - 1 -16 - 54 + 2 + 9 = (8 + 27) - 1 -16 -54 + 2 + 9 = 35 - 1 - 16 - 54 + 2 + 9 = 34 - 16 - 54 + 2 + 9 = 18 - 54 + 2 + 9 = -36 + 11 = -25\)
So the equation reduces to:
\[
2X^2 + 3Y^2 - Z^2 - 25 = 0
\]
or equivalently,
\[
2X^2 + 3Y^2 - Z^2 = 25
\]
Step 6: Write the transformed equation
After translation, the equation in the new coordinate system \((X, Y, Z)\) is:
\[
2X^2 + 3Y^2 - Z^2 = 25
\]
Final answer:
\[
2x^2 + 3y^2 - z^2 = 25
\]
(where \(x, y, z\) represent the new translated axes)