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If (a, b, c) is a point on the plane 3x...

If `(a, b, c)` is a point on the plane `3x + 2y + z = 7,` then find the least value of 2(`a^2+b^2+c^2),` using vector method.

Text Solution

Verified by Experts

The correct Answer is:
`7`
Clearly minimum value of `a^(2)+b^(2)+c^(2)`
`" " =((|(3(0)+ 2(0)+ (0)-7)|)/(sqrt((3)^(2)+ (2)^(2)+(1)^(2))))^(2) = (49)/(14)=(7)/(2)` units
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