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Use the cosine rule to find the value of angle A.
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A = Round your answer to 2 decimal places.question.score feedback.none Expected answer: °
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To find the value of A we need to use the cosine rule.
$\cos(\var{dspchosenangle}) = \frac{\var{side_dsp_vals[helpingvar]}^2 + \var{side_dsp_vals[othervar]}^2 - \var{side_dsp_vals[findvar]}^2}{2 \times \var{side_dsp_vals[helpingvar]} \times \var{side_dsp_vals[othervar]}}$
Take the inverse cos of both sides:
$\var{dspchosenangle} = \cos^{-1}(\frac{\var{side_dsp_vals[helpingvar]}^2 +\var{side_dsp_vals[othervar]}^2 -\var{side_dsp_vals[findvar]}^2}{2 \times \var{side_dsp_vals[helpingvar]} \times \var{side_dsp_vals[othervar]}}) = \var{precround(degrees(answer),2)}$°
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