Can someone help me with this problem.
Consider a quadratic function f(x) = 3x^2 - 9x + 4 and f(a)=f(b), where 'a' does not equal to 'b'.
Find the value of a+b.
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Can someone help me with this problem.
Consider a quadratic function f(x) = 3x^2 - 9x + 4 and f(a)=f(b), where 'a' does not equal to 'b'.
Find the value of a+b.
3x2 - 9x + 4 = 3[x2 - 3x] + 4
= 3(x - 3/2)2 - 27/4 + 4
Minimum point at (1.5, -2.75)
So a and b do not equal 1.5
To get the same value when put into the function they must be an equal distance from 1.5
So assume a < 1.5 and b > 1.5
Then 1.5 - a = b - 1.5
a + b = 3
ah thanks a lot for your help.