JAMB - Mathematics (1979 - No. 38)
If y = x\(^2\) - 2x - 3, find the least value of y and the corresponding value of x
x = 3, y = 3
x = 1, y = -3
x = 4, y = 1
x = 1, y = -4
x = 2, y = -3
설명
If the graph of eqn. y = x\(^2\) - 2x - 3 is plot and drawn, the lease value of y = -4 while the corresponding value of x = 1
x = 1, y = -4
OR
\(\frac{dy}{dx}\) = 0 = 2x - 2
2x = 2
x = 1
put x = 1 in y = 2x\(^2\) - 2x - 3
y = - 4
x= 1, y = -4