correct
do you know why ?
This is the last question on my homework and I wanted to know if I got it right. Thanks!
Which of the following inequalities is true for all real numbers of x?
a.) x^2≤x^3
b.) 2x^3≤4x^2
c.) 4x^2≤(4x)^2
d.) 4(x-3)^2≥4x^2-3
My answer: C.
3 answers
c.)
4 x ^ 2 ¡Ü ( 4 x ) ^ 2
4 x ^ 2 ¡Ü 16 x ^ 2 Subtract 4 x ^ 2 to both sides
4 x ^ 2 - 4 x ^ 2 ¡Ü 16 x ^ 2 - 4 x ^ 2
0 ¡Ü 12 x ^ 2 Divide both sides by 12
0 ¡Ü x ^ 2
This is equivalent of
0 ¡Ü x
0 < x
OR
0 > x
This is true for all real numbers.
4 x ^ 2 ¡Ü ( 4 x ) ^ 2
4 x ^ 2 ¡Ü 16 x ^ 2 Subtract 4 x ^ 2 to both sides
4 x ^ 2 - 4 x ^ 2 ¡Ü 16 x ^ 2 - 4 x ^ 2
0 ¡Ü 12 x ^ 2 Divide both sides by 12
0 ¡Ü x ^ 2
This is equivalent of
0 ¡Ü x
0 < x
OR
0 > x
This is true for all real numbers.
¡Ü
mean less or equal
mean less or equal