Q. Determine the following limit in simplest form. If the limit is infinite, state that the limit does not exist (DNE).x→∞lim3x+10x3−2+49x4Answer:
Identify highest power: We are asked to find the limit of the function (−2+49x4)/(3x+10x3) as x approaches infinity. To do this, we will first identify the highest power of x in both the numerator and the denominator.
Divide by x3: The highest power of x in the numerator inside the square root is x4, and in the denominator, it is x3. To simplify the limit, we will divide both the numerator and the denominator by x3, the highest power in the denominator.
Simplify expression: Dividing each term by x3 gives us the following expression:x→∞lim⎝⎛3+(10x2)x3−2+49x⎠⎞
Take square root: As x approaches infinity, the term (−x32) approaches 0, so we can simplify the expression to: x→∞lim(3+(10x2)49x)
Divide by x1/2: We can take the square root of 49x, which is 7x1/2, and rewrite the expression as:limx→∞3+(10x2)7x1/2
Approach infinity: Now, we divide the numerator and the denominator by x1/2, the highest power of x in the numerator: x→∞lim(3/x1/2+10x3/27)
Limit is 0: As x approaches infinity, the term x213 approaches 0, and we are left with: x→∞lim10x237
Limit is 0: As x approaches infinity, the term (3/x1/2) approaches 0, and we are left with:x→∞lim10x3/27Now, as x approaches infinity, the denominator (10x3/2) grows without bound, and the entire expression approaches 0. Therefore, the limit is 0.