Use square root and cube root symbols to represent solutions to equations

Start lessonBegins with Square roots cube roots irrational · Slides

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8.EE.A.2

**8.EE.A.2**: Use square root and cube root symbols to represent solutions to equations of the form x^2 = p and x^3 = p, where p is a positive rational number. Evaluate square roots of small perfect squares and cube roots of small perfect cubes. Know that sqrt2 is irrational.

8.EE.A.2: Use square root and cube root symbols to represent solutions to equations of the form x^2 = p and x^3 = p, where p is a positive rational number. Evaluate square roots of small perfect squares and cube roots of small perfect cubes. Know that sqrt2 is irrational.

What you'll learn

Use the square root symbol to represent solutions to equations of the form x^2 = p, distinguishing between the principal root sqrtp and the two solutions x = +/-sqrtp
Use the cube root symbol to represent solutions to equations of the form x^3 = p, recognizing that each such equation has exactly one real solution x = cbrtp
Evaluate square roots of perfect squares (1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144) and cube roots of perfect cubes (1, 8, 27, 64, 125) from memory
Evaluate square roots and cube roots of positive rational numbers that are perfect squares or perfect cubes, including fractions such as sqrt(1/4) = 1/2 and cbrt(1/8) = 1/2
Identify sqrt2 as irrational and explain that square roots of non-perfect-squares (such as sqrt3, sqrt5, sqrt7) are irrational numbers whose decimal expansions neither terminate nor repeat

Review first:

Know that numbers that are not rational are called irrational

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Square roots cube roots irrational

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