document.write( "Question 1023285: A ball is thrown into the air. The path of the ball is given by the quadratic formula h (t)= -4.9t^2+6.1t, where t is measured in seconds and h (t) in metres. How can i decide without completely solving this problem whether or not the ball will ever reach a height of 2 metres above the ground? \n" ); document.write( "
Algebra.Com's Answer #638795 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
-4.9t^2 means that ball follows a parabolic path that curves downward
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\n" ); document.write( "The first derivative is
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\n" ); document.write( "-9.8t +6.1
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\n" ); document.write( "Now set first derivative = 0
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\n" ); document.write( "-9.8t +6.1 = 0
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\n" ); document.write( "-9.8t = -6.1
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\n" ); document.write( "t is approx 0.6 seconds
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\n" ); document.write( "The ball reaches max height at 0.6 seconds
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\n" ); document.write( "h(0.6) = -4.9 (0.6)^2 +6.1 (0.6)
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\n" ); document.write( "max height reached is 1.9 meters
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\n" ); document.write( "The ball does not reach a height of 2 meters
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