document.write( "Question 1172398: What is the volume of solid in xyz-space bounded by surfaces y = x^2, y = 2 - x^2, z = 0 and z = y + 3? \n" ); document.write( "
Algebra.Com's Answer #850822 by CPhill(1959)![]() ![]() You can put this solution on YOUR website! Let's find the volume of the solid.\r \n" ); document.write( "\n" ); document.write( "**1. Determine the Region in the xy-Plane**\r \n" ); document.write( "\n" ); document.write( "* We need to find the intersection of the parabolas y = x^2 and y = 2 - x^2. \n" ); document.write( "* Set them equal: x^2 = 2 - x^2 \n" ); document.write( "* 2x^2 = 2 \n" ); document.write( "* x^2 = 1 \n" ); document.write( "* x = ±1 \n" ); document.write( "* When x = ±1, y = 1. \n" ); document.write( "* The region in the xy-plane is bounded by these parabolas, with x ranging from -1 to 1.\r \n" ); document.write( "\n" ); document.write( "**2. Set up the Triple Integral**\r \n" ); document.write( "\n" ); document.write( "* The volume is given by the triple integral: \n" ); document.write( " * V = ∫∫∫ dV \n" ); document.write( "* The limits of integration are: \n" ); document.write( " * z: 0 to y + 3 \n" ); document.write( " * y: x^2 to 2 - x^2 \n" ); document.write( " * x: -1 to 1\r \n" ); document.write( "\n" ); document.write( "* The integral becomes: \n" ); document.write( " * V = ∫(from -1 to 1) ∫(from x^2 to 2 - x^2) ∫(from 0 to y + 3) dz dy dx\r \n" ); document.write( "\n" ); document.write( "**3. Evaluate the Integral**\r \n" ); document.write( "\n" ); document.write( "* First, integrate with respect to z: \n" ); document.write( " * ∫(from 0 to y + 3) dz = [z](from 0 to y + 3) = y + 3 \n" ); document.write( "* Now, integrate with respect to y: \n" ); document.write( " * ∫(from x^2 to 2 - x^2) (y + 3) dy = [y^2/2 + 3y](from x^2 to 2 - x^2) \n" ); document.write( " * = [(2 - x^2)^2/2 + 3(2 - x^2)] - [(x^2)^2/2 + 3(x^2)] \n" ); document.write( " * = [4 - 4x^2 + x^4]/2 + 6 - 3x^2 - x^4/2 - 3x^2 \n" ); document.write( " * = 2 - 2x^2 + x^4/2 + 6 - 3x^2 - x^4/2 - 3x^2 \n" ); document.write( " * = 8 - 8x^2\r \n" ); document.write( "\n" ); document.write( "* Finally, integrate with respect to x: \n" ); document.write( " * ∫(from -1 to 1) (8 - 8x^2) dx = [8x - 8x^3/3](from -1 to 1) \n" ); document.write( " * = [8(1) - 8(1)^3/3] - [8(-1) - 8(-1)^3/3] \n" ); document.write( " * = [8 - 8/3] - [-8 + 8/3] \n" ); document.write( " * = 8 - 8/3 + 8 - 8/3 \n" ); document.write( " * = 16 - 16/3 \n" ); document.write( " * = (48 - 16)/3 \n" ); document.write( " * = 32/3\r \n" ); document.write( "\n" ); document.write( "**Answer**\r \n" ); document.write( "\n" ); document.write( "The volume of the solid is 32/3 cubic units. \n" ); document.write( " \n" ); document.write( " |