document.write( "Question 828022: A projectile follows a parabolic path whose height, in meters, is given by the function f(x) = -x^2 + 2x +2. Find the maximum horizontal distance that the projectile may cover.
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Algebra.Com's Answer #499069 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"+f%28x%29+=+-x%5E2+%2B+2x+%2B2+\"$
\n" ); document.write( "The horizontal distance, $\"x\"$ , is
\n" ); document.write( "greatest at $\"+f%28x%29+=+0+\"$ where $\"+f%28x%29+\"$
\n" ); document.write( "is the height
\n" ); document.write( " $\"+-x%5E2+%2B+2x+%2B+2++=+0+\"$
\n" ); document.write( "Use the quadratic formula
\n" ); document.write( " $\"+x+=+%28+-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29+%2F+%282%2Aa%29+\"$
\n" ); document.write( " $\"+a+=+-1+\"$
\n" ); document.write( " $\"+b+=+2+\"$
\n" ); document.write( " $\"+c+=+2+\"$
\n" ); document.write( " $\"+x+=+%28+-2+%2B-+sqrt%28+2%5E2+-+4%2A%28-1%29%2A2+%29%29+%2F+%282%2A%28-1%29%29+\"$
\n" ); document.write( " $\"+x+=+%28+-2+%2B-+sqrt%28+4+%2B+8+%29%29+%2F+%28-2%29+\"$
\n" ); document.write( " $\"+x+=+%28+-2+-+2%2Asqrt%28+3+%29+%29+%2F+%28-2+%29+\"$
\n" ); document.write( " $\"+x+=+1+%2B+sqrt%283%29+\"$
\n" ); document.write( " $\"+x+=+1+%2B+1.732+\"$
\n" ); document.write( " $\"+x+=+2.732+\"$ maximum distance of projectile
\n" ); document.write( "Notice that I used the minus square root to get
\n" ); document.write( "the greatest possible positive result
\n" ); document.write( "Here's the plot:
\n" ); document.write( " $\"+graph%28+400%2C+400%2C+-1%2C+4%2C+-1%2C+4%2C+-x%5E2+%2B+2x+%2B+2+%29+\"$ \r
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