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2 votes
The choices for the first one is

1/4

1

5/4

Choice for the second one is
(3i square root 7)/4

(i square root 21)/2

(square root 112)/4

The choices for the first one is 1/4 1 5/4 Choice for the second one is (3i square-example-1

1 Answer

3 votes

Answer:


\large\boxed{(5\pm3\sqrt7)/(4)}

Explanation:


m^2-(5)/(2)m=-(11)/(2)\qquad\text{add}\ (11)/(2)\ \text{to both sides}\\\\m^2-(5)/(2)m+(11)/(2)=0\qquad\text{multiply both sides by 2}\\\\2m^2-5m+11=0


\text{Use the quadratic formula:}


ax^2+bx+c=0\\\\x=(-b\pm√(b^2-4ac))/(2a)


\text{We have}


a=2,\ b=-5,\ c=11


\text{substitute:}


√(b^2-4ac)=√((-5)^2-4(2)(11))=√(25-88)=√(63)=√(9\cdot7)=\sqrt9\cdot\sqrt7=3\sqrt7\\\\m=(-(-5)\pm3\sqrt7)/(2(2))=(5\pm3\sqrt7)/(4)

User DCTID
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