Can someone explain this to me?
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Answer:
Step-by-step explanation:
a). By applying tangent rule in the triangle,
tanθ = [tex]\frac{\text{Opposite side}}{\text{Adjacent side}}=\frac{3}{4}[/tex]
θ = [tex]\text{tan}^{-1}(\frac{3}{4})[/tex]
θ = 36.87°
Therefore, θ < 45°
b). By using cosine rule in this triangle,
cosθ = [tex]\frac{\text{Adjacent side}}{\text{Hypotenuse}}=\frac{18}{18\sqrt{2}}[/tex]
cosθ = [tex]\frac{1}{\sqrt{2}}[/tex]
θ = 45°
c). By using tangent rule,
tanθ = [tex]\frac{\text{Opposite side}}{\text{Adjacent side}}=\frac{8}{2}[/tex]
θ = [tex]\text{tan}^{-1}(4)[/tex]
θ = 75.96°
θ > 45°