Problem Solving (PS) | Re: If y = (x – 5)^2 + (x + 1)^2 – 6, then y is least when x =

Option:D
Time Taken:1:34
here you go
y=(x-5)^2+(x+1)^2-6[expand using formula(a-b)^2 and (a+b)^2]
y=x^2-10x+25+x^2+2x+1-6
y=2x^2-8x+20
Divide by
y=x^2-4x+10
Since we need to find least so putting negative values wont make sense keeping in powers and negative sign with co-efficient
start with "0"
y=10
then "2"
y=4-8+10
y=6

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