Cosine
Cosine and sine theorem:
Calculate all unknown values (side lengths or angles) from triangle ABC.
c = 2.9 cm; β = 28°; γ = 14° α =? °; a =? cm; b =? cm
Calculate all unknown values (side lengths or angles) from triangle ABC.
c = 2.9 cm; β = 28°; γ = 14° α =? °; a =? cm; b =? cm
Correct answer:

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Cosine rule uses trigonometric SAS triangle calculator.
See also our trigonometric triangle calculator.
Try conversion angle units angle degrees, minutes, seconds, radians, grads.
Do you want to convert length units?
Do you want to convert time units like minutes to seconds?
Cosine rule uses trigonometric SAS triangle calculator.
See also our trigonometric triangle calculator.
Try conversion angle units angle degrees, minutes, seconds, radians, grads.
You need to know the following knowledge to solve this word math problem:
- algebra
- isolating a variable in the formula
- planimetrics
- triangle
- The Law of Cosines
- The Law of Sines
- basic functions
- percentages
- goniometry and trigonometry
- sine
- cosine
Units of physical quantities:
Grade of the word problem:
We encourage you to watch this tutorial video on this math problem: video1
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