5 IdentifyZerosandTheirMultiplicities
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
Findthezerosforthepolynomialfunctionandgivethemultiplicityforeachzero.Statewhetherthegraphcrossesthe
x–axisortouchesthex–axisandturnsaround,ateachzero.
1) f(x)=2(x+1)(x+2)4
A) –1
multiplicity1,crossesx–axis;–2
multiplicity4
touchesx–axisandturnsaround
B) 1
multiplicity1,crossesx–axis;2
multiplicity4
touchesx–axisandturnsaround
C) –1
multiplicity1,touchesx–axisandturnsaround;–2
multiplicity4
crossesx–axis
D) 1
multiplicity1,touchesx–axisandturnsaround;2
multiplicity4
crossesx–axis
2) f(x)=4(x+6)(x+5)3
A) –6
multiplicity1,crossesx–axis;–5
multiplicity3,crossesx–axis
B) 6
multiplicity1,crossesx–axis;5
multiplicity3,crossesx–axis
C) –6
multiplicity1,crossesx–axis;–5
multiplicity3,touchesx–axisandturnsaround
D) 6
multiplicity1,touchesx–axis;5
multiplicity3,touchesx–axisandturnsaround
3) f(x)=4x+2(x–2)3
A) –2
multiplicity1,crossesx–axis;2
multiplicity3,crossesx–axis
B) 2
multiplicity1,crossesx–axis;–2
multiplicity3,crossesx–axis
C) –2
multiplicity1,touchesthex–axisandturnsaround;2
multiplicity3,touchesx–axisandturns
around
D) 2
multiplicity1,touchesthex–axisandturnsaround;–2
multiplicity3,touchesx–axisandturnsaround
4) f(x)=3(x2+2)(x–1)2
A) 1
multiplicity2,touchesthex–axisandturnsaround
B) –2
multiplicity1,crossesthex–axis;1
multiplicity2,touchesthex–axisandturnsaround.
C) –2
multiplicity1,crossesthex–axis;1
multiplicity2,crossesthex–axis
D) 1
multiplicity2,crossesthex–axis
5) f(x)=1
4x4(x2–3)(x–7)
A) 0,multiplicity4
touchesx–axisandturnsaround;
7,multiplicity1,crossesx–axis;
3,multiplicity1,crossesx–axis;
–3,multiplicity1,crossesx–axis
B) 0,multiplicity4
crossesx–axis;
7,multiplicity1,touchesx–axisandturnsaround;
3,multiplicity1,touchesx–axisandturnsaround;
–3,multiplicity1,touchesx–axisandturnsaround
C) 0,multiplicity4
touchesx–axisandturnsaround;
7,multiplicity1,crossesx–axis
D) 0,multiplicity4
touchesx–axisandturnsaround;
7,multiplicity1,crossesx–axis
3,multiplicity2,touchesx–axisandturnsaround
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