Determine the following limit in simplest form. If the limit is infinite, state that the limit does not exist (DNE).x→∞lim5x+9x2+93−19x3−27x6Answer:
Q. Determine the following limit in simplest form. If the limit is infinite, state that the limit does not exist (DNE).x→∞lim5x+9x2+93−19x3−27x6Answer:
Factor out highest power: We are given the limit expression limx→∞(3−19x3−27x6)/(5x+9x2+9). To simplify this, we will first factor out the highest power of x in the numerator and denominator.
Rewrite with factored terms: In the numerator, the highest power of x inside the cube root is x6. We factor out x6 from each term inside the cube root.3−19x3−27x6=3x6(−x319−27)
Simplify cube root: In the denominator, the highest power of x is x2. We factor out x2 from each term.5x+9x2+9=x2(x5+9+x29)
Divide by x2: Now we rewrite the limit expression with the factored terms.x→∞lim⎝⎛x2(x5+9+x29)3x6(−x319−27)⎠⎞
Approaching infinity: We can simplify the cube root of x6 as x2 because (x2)3=x6.3x6(−x319−27)=x2⋅3−x319−27
Find limit: Now we divide both the numerator and the denominator by x2. x→∞lim⎝⎛x2(x5+9+x29)x23−x319−27⎠⎞=x→∞lim⎝⎛x5+9+x293−x319−27⎠⎞
Calculate cube root: As x approaches infinity, the terms with x in the denominator approach 0. limx→∞(3−x319−27)=3−27 limx→∞(x5+9+x29)=9
Divide to get limit: Now we can find the limit of the simplified expression. limx→∞(x5+9+x293−x319−27)=93−27
Divide to get limit: Now we can find the limit of the simplified expression.limx→∞(5/x+9+9/x23−19/x3−27)=93−27The cube root of −27 is −3.3−27=−3
Divide to get limit: Now we can find the limit of the simplified expression.limx→∞(5/x+9+9/x23−19/x3−27)=93−27The cube root of −27 is −3.3−27=−3Finally, we divide −3 by 9 to get the limit.−93=−31