Multiply by Conjugate: To resolve the indeterminate form, we can multiply the expression by the conjugate of the denominator over itself, which is a common technique for limits involving square roots.limx→34x+4−4x−3⋅4x+4+44x+4+4This multiplication is valid because 4x+4+44x+4+4 is equal to 1, and multiplying by 1 does not change the value of the expression.
Simplify Numerator and Denominator: Now, we simplify the numerator and the denominator separately.Numerator:(x−3)(4x+4+4)Denominator:(4x+4−4)(4x+4+4)The denominator simplifies to the difference of squares:(4x+4)2−(4)2=4x+4−16=4x−12
Distribute and Combine Like Terms: Next, we simplify the numerator by distributing x−3 to both terms inside the parentheses.Numerator:x4x+4+4x−34x+4−12Now, we can combine like terms in the numerator:x4x+4−34x+4+4x−12= (x−3)4x+4+4x−12
Cancel Common Terms: We now have the following expression for the limit: limx→3(4x−12(x−3)(4x+4)+4x−12) Notice that the term (x−3) in the numerator will cancel out the (4x−12) in the denominator when x approaches 3, because 4x−12factors to 4(x−3).
Factor Out and Simplify: Let's factor out the 4 in the denominator and cancel out the common (x−3) terms:\lim_{x \to 3}\frac{(x−3)(\sqrt{4x+4}) + 4x - 12}{4(x - 3)}= \lim_{x \to 3}(\sqrt{4x+4}) + 4Now, we can directly substitute x=3 into the simplified expression:= (\sqrt{4\cdot 3+4}) + 4= (\sqrt{12+4}) + 4= (\sqrt{16}) + 4= 4 + 4= 8
Substitute and Calculate: Since the original expression simplifies to 8 as x approaches 3, the correct answer is not among the provided options (A)−4, (B)1, (C)2, or (D) The limit doesn't exist. There seems to be a mistake in the provided options.
More problems from Add, subtract, multiply, and divide polynomials