Find the solutions of the followingg quadratic functions Fin
Find the solutions of the followingg quadratic functions:
Find the domain and range of each of the following function:
Domain:
Range:
Domain:
Range:
Solution
a) -3x^2 +2x +8 =0
factorise : -3x^2 +6x -4x +8 =0
-3x(x-2) -2(x-2) =0
(-3x -2)(x-2) =0
-3x = 2----> x= -2/3
x=2
Solution : x= -2/3 , 2
b) 2(x+3)^2 = 32
(x+3)^2 = 16
take square root on both sides:
x+3 = +/- 4
x = -7 , 1
a) f(t) = sqrt(4-7t)
Domain: 4 -7t >=0
7t<=4 ---->t <= 4/7
(- inf , 4/7)
Range : f(t) =0
[ 0, inf)
g(x) = -x^2 +9
Domain: all real (- inf, inf)
Range : y interecpt : y =9 and its an inverted parabola
So, (-inf ,9]
