document.write( "Question 102561: If f(x)= x(x+1) (x-4), use interval notation to give all values of x where f(x) >0. \n" ); document.write( "

Algebra.Com's Answer #74603 by Nate(3500) $\"\"$ $\"About$

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f(x) = x(x + 1)(x - 4)
\n" ); document.write( "For x = 0, x = -1, and x = 4, f(x) has the value of zero.
\n" ); document.write( "<----------(-1)---------(0)-------------------------(4)-------->
\n" ); document.write( "Test:
\n" ); document.write( "f(-2) = -2(-1)(-6) = -12
\n" ); document.write( "f(-1/2) = (-1/2)(1/2)(-9/2) = 9/8
\n" ); document.write( "f(1) = (2)(-3) = -6
\n" ); document.write( "f(5) = 5(6)(1) = 30
\n" ); document.write( "<----------(-1)=========(0)-------------------------(4)========>
\n" ); document.write( "f(x) > 0 only satisfied by f(x) > 4 and 0 > f(x) > -1
\n" ); document.write( "or
\n" ); document.write( "(-1,0)U(4,+ $\"inf\"$ )
\n" ); document.write( " $\"graph%28300%2C300%2C-5%2C5%2C-5%2C5%2Cx%5E3+-+3x%5E2+-+4x%29\"$ \n" ); document.write( "

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