Q19 of 45 Page 1

Using vectors, find the area of the triangle ABC, whose vertices are A (1, 2, 3), B (2, –1, 4) and C (4, 5, –1).

Formula:- (i) area of triangle =


(ii)subtraction of vector



(iii)multiplication of vector



(iv) IF


Given:-




And


Using the formula of (ii)








Now let us determine



Using formula (iii)



……………………………using formula (iv)



Area of a triangle is


Area of a triangle is sq.unit


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