Q16 of 39 Page 150

In ΔABC, ∠BAC = 90° and BCA = 30°; Lets prove that AB = 1/2 BC

Given: ΔABC, ∠BAC = 90° and BCA = 30°


To prove:


The figure for the above question is as shown below,



Given ΔABC is a right - angled triangle, now applying the properties of the triangle,


We know



Now when θ = 30°, AB is the opposite side and BC is the hypotenuse, then the above equation becomes,



Now we know the value of , substituting this in above equation, we get




Hence proved


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