Im so confused :( f(x)=(x^2+4)(3-2x)^2 Solve the inequality for a) f(x)>0 b) f(x)≥0 c) f(x)<0 d) f(x)≤0 Im so confused :( f(x)=(x^2+4)(3-2x)^2 Solve the inequality for a) f(x)>0 b) f(x)≥0 c) f(x)<0 d) f(x)≤0 @Mathematics
ok first term is always positive because \[x^2\geq0\] and so \[x^2+4\geq 4\]
so you can safely ignore that term completely
\[(3-2x)^2>0\] for all x except \[x=\frac{3}{2}\] in which case you get 0
ignore what term and how do u know it is ≥ and not >?
you can ignore \[x^2+4\] because it is always greater than or equal to 4, so it is always greater than 0
ok
so the whole thing \[(x^2+4)(3-2x)^2\] is always greater than or equal to zero, and it is always greater then zero unless x = 3/2 now lets answer each question in turn.
\[a) f(x)>0\] all x except 3/2
so x cannot equal 3/2 correct?
for that one yes, because if x = 3/2 you get 0
\[b) f(x)≥0 \] true for all x
\[f(x)<0\] never true
\[d) f(x)≤0 \] only true if x = 3/2
so d would be written as (-inf, 3/2]?
Join our real-time social learning platform and learn together with your friends!