Answer:
y = -x⁴ + x² - 2 : D
y = x⁵ + x² + 7 : B
y = x⁶ + 2x³ + 3 : C
Step-by-step explanation:
anyways look at the part with the largest power of x. it will have the biggest impact on the overall value, when x approaches positive or negative infinity.
in the first one this is -x⁴
x⁴ is always positive (for positive and negative x). so, -x⁴ is always negative. therefore, it decreases in both cases when x approaches positive or negative infinity.
in the second one this is x⁵.
this goes with the sign of x. it is getting bigger (it increases), when x approaches positive infinity, and it is getting smaller (it decreases), when x approaches negative infinity.
in the third one this is x⁶.
this is always positive (for positive and negative x). therefore, it increases in both cases when x approaches positive or negative infinity.
