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प्रश्न
From the figure, given below, calculate the length of CD.
उत्तर
In right ΔACB, we have
`tan theta = (AB)/(BC)`
`\implies tan 47^circ = (AB)/15`
`\implies 1.0724 = (AB)/15`
∴ AB = 1.0724 × 15
= 16.0860 m
= 16.09 m.
And in right ΔADE, we have
`tan 22^circ = (AE)/(DE)`
`\implies 0.4040 = (AE)/15`
∴ AE = 15 × 0.4040
= 6.0600
= 6.06 m.
∴ CD = EB
= AB – AE
= 16.09 – 6.06
= 10.03 m
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