Given a=9, b=40, and c=41, we are trying to find angle B.
Using the Law of Cosines:
b^2 = a^2 + c^2 - 2ac * cosB
(40)^2 = (9)^2 + (41)^2 - 2(9)(41) * cosB
1600 = 81 + 1681 - 738 * cosB
1600 = 1762 - 738 * cosB
-162 = -738 * cosB
cosB = 162/738
cosB = 0.21951
Therefore, angle B is equal to cos^(-1)(0.21951) ≈ 77.004°.
Use the Law of Cosines, b2=a2+c2−2ac⋅cosB, to find the value of angle B in a right triangle, where a=9, b=40, and c=41.
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