Index notation

你需要知道的

• In 5², the 5 is the base and the 2 is the power (index), which says how many 5s to multiply together.
• 5² means 5 × 5 = 25, not 5 × 2 = 10.
• A power of 2 is read 'squared' and a power of 3 is read 'cubed'.
• Repeated multiplication such as 3 × 3 × 3 × 3 × 3 × 3 can be written as 3⁶, which equals 729.

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