Cosine Law
10 tutor-authored questions for this Ontario curriculum expectation, ordered easiest to hardest — every one with a full worked solution. Work through them free, no account needed.
Sample: the first question, solved
In the formula a² = b² + c² − 2bc·cos(A), which angle does the "A" refer to?
📘 Worked solution
✓It's the angle opposite side a — the cosine law always pairs the squared side on the left with the angle across from it on the right.
And one from the hard end
In triangle ABC, a=7, b=9, c=12. Find angle C.
Solution shown after you try it in practice mode.
Work through all 10, easiest to hardest
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