document.write( "Question 65470: f(x)=x(x+3)(x-1) use interval notation to give all values of x where f(x)>0 \n" ); document.write( "

Algebra.Com's Answer #46024 by funmath(2933) $\"\"$ $\"About$

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f(x)=x(x+3)(x-1) use interval notation to give all values of x where f(x)>0
\n" ); document.write( "f(x)=0 when:
\n" ); document.write( "x=0 or x+3=0 or x-1=0
\n" ); document.write( "x=0 or x=-3 or x=1
\n" ); document.write( "Therefore, the intervals to test are:
\n" ); document.write( "(-infinity,-3) or (-3,0) or (0,1) or (1,infinity)
\n" ); document.write( "For (-infinity,-3) test -4:
\n" ); document.write( "f(-4)=-4(-4+3)(-4-1)=-4(-1)(-5)=-20 <--negative, reject this interval
\n" ); document.write( "For (-3,0) test -1:
\n" ); document.write( "f(-1)=-1(-1+3)(-1-1)=-1(2)(-2)=4 <--positive, accept this interval
\n" ); document.write( "For (0,1) test .5
\n" ); document.write( "f(.5)=.5(.5+3)(.5-1)=.5(3.5)(-.5) -.875 <--negative reject this interval
\n" ); document.write( "For (1, infinity) test 2:
\n" ); document.write( "f(2)=2(2+3)(2-1)=2(5)(1)=10 <--positive, accept this interval
\n" ); document.write( "Therefore your solution is:
\n" ); document.write( "(-3,0)U(1,infinity)
\n" ); document.write( "Happy Calculating!!! \n" ); document.write( "

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