Question

Ajutama va rog frumoas la ex:9 (e si f)

Answer 1

f(x)= 4(x+2)^2-6
f(x)= 4( x^2+2*x*2+2^2)-6
f(x)= 4(x^2+4x+4)-6
f(x)= 4x^2+16x+16-6
f(x)= 4x^2+16x+12
∆=b^2-4ac
a=4
b= 16
c=12
∆= 256-192
∆= 64
√∆=8
x1= -b+√∆/2a
x1= (-16+8)/2*4
x1= -8/8
x1=-1
x2= (-16-8)/8
x2= -24/8
x2= -3
f) f(x)= -(x-3)^2+2
f(x) = -(x^2-2*3x+3^2)
f(x)= -(x^2-6x+9)
f(x)= -x^2+6x-9
∆= 36-(4*(-1)*(-9))
∆= 36-36
∆=0
x= -6+0/2*(-1)
x=-6/-2
x=3