Factorizing quadratic expressions is the opposite of multiplying out the brackets. For example the expression (x+1)(x+3) can be multiplied out to give x^2+4x+3. Going the other way or reversing this process is called factorizing.
The ability to factorize quadratic functions is essential to making sound progress in advanced mathematics. It is a skill. You get better with practice.
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A mathematical expression of the 2nd degree; having a x² term but no higher one.
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