Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

If a^3bc^2 < 0, which of the following must be correct?\newline(A) a < 0 \& c < 0\newline(B) b < 0 \& c < 0\newline(C) a < 0 \& b > 0\newline(D) a < 0 \& b > 0 or a > 0 \& b < 0

Full solution

Q. If a3bc2<0a^3bc^2 < 0, which of the following must be correct?\newline(A) a<0&c<0a < 0 \& c < 0\newline(B) b<0&c<0b < 0 \& c < 0\newline(C) a<0&b>0a < 0 \& b > 0\newline(D) a<0&b>0a < 0 \& b > 0 or a>0&b<0a > 0 \& b < 0
  1. Analyze inequality signs: Analyze the given inequality a^3 \cdot b \cdot c^2 < 0. Since a3a^3 is cubed, it will have the same sign as aa. The term c2c^2 is squared, so it will always be non-negative (zero or positive). Therefore, the sign of the inequality is determined by the signs of aa and bb.
  2. Consider sign combinations: Consider the possible sign combinations for aa and bb that would make the inequality true.\newlineIf aa is positive, then bb must be negative to make the product negative because c2c^2 is always non-negative.\newlineIf aa is negative, then bb must be positive to make the product negative because c2c^2 is always non-negative.
  3. Match with options: Match the possible sign combinations to the given options.\newlineOption (A) states a < 0 and c < 0, but cc's sign does not matter since c2c^2 is always non-negative.\newlineOption (B) states b < 0 and c < 0, but this does not consider the sign of aa.\newlineOption (C) states a < 0 and b > 0, which is one possible correct combination.\newlineOption (D) states a < 0 \& b > 0 or c < 000, which includes both possible correct combinations.
  4. Determine correct answer: Determine the correct answer based on the analysis.\newlineOption (D) is the only option that includes all possible correct sign combinations for aa and bb that satisfy the inequality a^3 \cdot b \cdot c^2 < 0.

More problems from Solve quadratic inequalities