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Question
In the adjoining figure, ΔABC is right-angled at B and ∠A = 450. If AC = 3`sqrt(2)`cm, find (i) BC, (ii) AB.
Solution
From the right-angled ΔABC, we have:
`(BC)/(AC) = sin 45^0`
⇒ `(BC)/(3sqrt(2)) = 1/sqrt(2) `⇒ BC = 3cm
Also, `(AB)/(AC) = cos 45^0`
⇒` (AB)/(3sqrt(2)) = 1/sqrt(2)` ⇒ AB = 3 cm
∴ BC = 3 cm and AB = 3 cm
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