document.write( "Question 1189385: a rocket is launched from the ground with an initial velocity of 48 feet per second, so that its distance in feet above the ground after t seconds is s(t)=-16t^2+48t. what is the maximum height of the rocket \n" ); document.write( "

Algebra.Com's Answer #820727 by ikleyn(52794) $\"\"$ $\"About$

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\n" ); document.write( "a rocket is launched from the ground with an initial velocity of 48 feet per second,
\n" ); document.write( "so that its distance in feet above the ground after t seconds is s(t)=-16t^2+48t.
\n" ); document.write( "what is the maximum height of the rocket
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document.write( "The function s(t) = -16t^2 + 48t  is a quadratic function, whose plot is a parabola opened down.\r\n" );
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document.write( "This quadratic function has the maximum at the value of its argument  t = , where \r\n" );
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document.write( "\"a\" is the coefficient at  t^2  and \"b\" is the coefficient at t.\r\n" );
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document.write( "In your case, a= -16,  b= 48, so the function gets the maximum at  t =  = 1.5 seconds.\r\n" );
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document.write( "So, the ball gets the maximum height  1.5 seconds after is hit straight up. \r\n" );
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document.write( "The maximum height is then  s(1.5) = - 16*1.5^2 + 48*1.5 = 36 feet.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "To see many other similar solved problems, slook into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Problem on a projectile moving vertically up and down\r
\n" ); document.write( "\n" ); document.write( "    - Problem on an arrow shot vertically upward\r
\n" ); document.write( "\n" ); document.write( "    - Problem on a ball thrown vertically up from the top of a tower \r
\n" ); document.write( "\n" ); document.write( "    - Problem on a toy rocket launched vertically up from a tall platform\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "On finding the maximum/minimum of a quadratic function, learn from the lessons \r
\n" ); document.write( "\n" ); document.write( "    - HOW TO complete the square to find the minimum/maximum of a quadratic function\r
\n" ); document.write( "\n" ); document.write( "    - Briefly on finding the minimum/maximum of a quadratic function\r
\n" ); document.write( "\n" ); document.write( "    - HOW TO complete the square to find the vertex of a parabola\r
\n" ); document.write( "\n" ); document.write( "    - Briefly on finding the vertex of a parabola\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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