153k views
25 votes
F(x)=(x+3)^2 -8 how many real solutions?

User Altaf Sami
by
4.4k points

1 Answer

5 votes

Answer:

2 real solutions

Explanation:


f(x)=(x+3)^2-8\\\\0=(x+3)^2-8\\\\8=(x+3)^2\\\\\pm√(8)=x+3\\\\x=-3\pm√(8)

Therefore, the function set at
f(x)=0 has two real solutions (x-intercepts).

You can also check the discriminant of the function by expanding it:


(x+3)^2-8=x^2+6x+9-8=x^2+6x+1\\\\b^2-4ac=6^2-4(1)(1)=36-4=32 > 0

Since it's greater than 0, there's two real solutions

User Jukzi
by
4.5k points