Law of cosines, an Uncommon card

The card carries these facts from its Wikipedia article.

• For a triangle with sides ⁠ a ⁠, ⁠ b ⁠, and ⁠ c ⁠, opposite respective angles ⁠ α ⁠, ⁠ β ⁠, and ⁠ γ ⁠, the law of cosines states: c 2 = a 2 + b 2 − 2 a b cos ⁡ γ, a 2 = b 2 + c 2 − 2 b c cos ⁡ α, b 2 = a 2 + c 2 − 2 a c cos ⁡ β.
• The law of cosines is useful for solving a triangle when all three sides or two sides and their included angle are given.

Rarity in WikiCards follows a year of Wikipedia page views: the most read articles become Epic and Legendary cards. The Law of cosines article was read about 160,000 times in a year. ATK comes from the length of the article and DEF from its quality, so this card hits with 73 and blocks with 63: each hit it takes is cut by 25 %.

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The cards just above and just below Law of cosines in the power ranking, all domains together.