If y= (x-1)(x+2), then what is the least possible value of y?
Any alternative solutions?
The function is a parabola with a positive "a" coefficient
The roots are x=1 and x=-2, for values between 1 and -2 it will have negative values (E is out)y=x^2+x-2
, you can try to insert values (starting from the least) to see if it could be the answer. Example-3=x^2+x-2
valid => CORRECTOr approach #2:
Given the roots -2 and 1, the x of the vertex will be the middle point => x=-0.5
And the least value will be the y coordinate of the vertex (plug x=-0.5
into the equation).
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