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#### a)

\n

$\\var{a}+\\var{b} = \\var{a+b}$

\n

#### b)

\n

$\\var{a} \\times \\var{b} = \\var{a*b}$

\n

#### c)

\n

Using the method of completing the square:

\n

\\begin{align}
\\simplify{x^2 + {qb}*x + {qc}} = \\simplify[std]{(x+{qb/2})^2 - {qb^2/4} + {qc}} &= \\simplify[std]{(x+{qb/2})^2}-\\left(\\simplify[std]{({sqrt(qb^2/4 - qc)})}\\right)^2 \\\\
&= \\simplify[std,!collectNumbers]{(x+{qb/2}-{sqrt(qb^2/4 - qc)})(x+{qb/2}+{sqrt(qb^2/4 - qc)})} & \\text{(difference of two squares)} \\\\
&= \\simplify[std]{(x+{qb/2}-{sqrt(qb^2/4 - qc)})(x+{qb/2}+{sqrt(qb^2/4 - qc)})}
\\end{align}

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What is $\\var{a}+\\var{b}$?

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What is $\\var{c} \\times \\var{d}$?

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Factorise $\\simplify{ x^2 + {x0+x1}*x + {x0*x1} }$.

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The question created during the \"Write your first question\" tutorial.

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