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If the base angles of triangle are (22)/...

If the base angles of triangle are `(22)/(12)a n d112 1/2^0` , then prove that the altitude of the triangle is equal to `1/2` of its base.

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In `Delta ABC, (BC)/(sin 45^(@)) = (AC)/(sin 22 (1)/(2)@)`
In `Delta ALC, (AL)/(AC) = sin 67 (1)/(2)@`

`AL = AC cos 22 (1)/(2)@`
`= (BC) /(sin 45^(@)) sin 22 (1)/(2)@ cos 22 (1)/(2)@` [using Eq. (i)]
`= (1)/(2) BC (sin 45^(@))/(sin 45^(@))`
`= (1)/(2) BC = (1)/(2) xx` Base
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