In ΔABC, m∠ACB = 90°, CD ⊥ AB and m∠ACD = 45°. Find: CD, if BC = 3 in
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The length of CD is determined by using trignometry functions. In the given triangle ABC the length of CD is 2.1213.
Given :
In trignometry functions, cosine is the ratio of the base to the hypotenuse. So, from triangle DCB the length of CD can be evaluated as:
[tex]\rm cos45^\circ =\dfrac{CD}{CB}[/tex]
[tex]\rm cos45^\circ =\dfrac{CD}{3}[/tex]
Now, put the value of [tex]\rm cos45^\circ[/tex] which is [tex]1\div \sqrt{2}[/tex] in above equation.
[tex]\rm \dfrac{1}{\sqrt{2} } = \dfrac{CD}{3}[/tex]
[tex]\rm CD = \dfrac{3}{\sqrt{2} }=2.1213[/tex]
In the given triangle ABC the length of CD is 2.1213.
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