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RE: Worksheet 3

funtion is-x^2-4x-5
answer questions below
a.Domain(interval notaion)
b.Range(interval notation)
c.The function is Increasing on the interval(answer in interval notaion)
   or the function is never increasing
d. the function is Decreasing on the interval(answer in interval notation)
    or the function is never decreasing

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Teodor M. | A++ Perfect Grade Math Science ACT ASVAB GRE GMAT FRE/SPAA++ Perfect Grade Math Science ACT ASVAB...
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x^2 -4x -5
We know it is a parabola
we know it faces up
we know the zeros or factors are "-" and a "+" and the "-" is greater
it factors to: (x-5)(x+1)
the zeros are x=5, -1 this is where the parabola crosses the x-axis and the y is zero
take the differential to find the vertex 2x-4 = 0, x=2 therefore y= -9 The lowest point is (2,-9)
the domain -s (-OO, OO)
the range is [-9, OO)
It decreases in Y from -OO to 2 on the x
It increases in Y from 2 to +OO on the x