maths.free › Algebra › Simplifying expressions

Simplifying expressions

Cancelling common factors and combining fractions.

To simplify a rational expression, factor the numerator and the denominator and cancel what they share: remembering the cancelled factor still forbids the value that made it zero. Sums of fractions are combined over a common denominator, just like numbers.

Работен пример · simplify (x^2-1)/(x-1)

Simplify (x^2 - 1)/(x - 1)

\frac{x^{2} - 1}{x - 1}

Стъпка по стъпка

  1. \frac{x^{2} - 1}{x - 1}

    Start from the expression.

  2. x + 1

    Factor numerator and denominator and cancel common factors.

Разкрийте отговора
x + 1

Сега ти. Изберете проблем, или тип или нарисувате собствен. Всяка стъпка, снимка, отговор скрит, докато не попитате.

Запази си работата.

Безплатна сметка добавя бележки за всеки урок, запис на това, което сте завършили, решавате проблеми на едно място, и учител, който можете да попитате за тази страница. Самата математика е отворена за всеки, подписан или не.

Записване Вход

Символи, използвани тук

Докоснете всеки символ за пълното определение, снимка и какво означава всяка буква в него.

Как да се: Simplifying expressions

  1. Start from the expression.
  2. Factor numerator and denominator and cancel common factors.

Въпроси, които хората задават

What does it mean to solve an equation?

To find every value of the unknown that makes both sides equal. Each step is an operation applied to both sides that keeps the solution set the same, until the unknown stands alone.

Why do I sometimes get two answers?

A quadratic can cross the axis twice, so it can have two solutions. A degree-n polynomial has up to n. The graph shows where each one comes from.

How do I know whether to factor or use the quadratic formula?

Try factoring for a few seconds: look for two numbers that multiply to a·c and add to b. If nothing obvious appears, the discriminant b² − 4ac tells you how many real roots there are, and the formula finds them without guessing.

Още в Algebra