Let p, q (p \gt q) be the roots of the quadratic equation x^{2}+bx+c=0 where c \gt 0. If p^{2}+q^{2}-11pq=0, then what is p-q equal to?
- A. 3\sqrt{c} ✓
- B. 3c
- C. 9\sqrt{c}
- D. 9c
Correct Answer: A. 3\sqrt{c}
Explanation
Let p and q be the roots. We have p+q = -b and pq = c. Given p^2+q^2-11pq = 0, we subtract 2pq from both sides to form a perfect square: p^2+q^2-2pq = 9pq. This implies (p-q)^2 = 9c. Since p \gt q, p-q must be positive, so p-q = 3\sqrt{c}.
Related questions on Algebra
- How many four-digit natural numbers are there such that <strong>ALL</strong> of the digits are odd?
- What is \sum_{r=0}^{n}2^{r}C(n,r) equal to ?
- If different permutations of the letters of the word 'MATHEMATICS' are listed as in a dictionary, how many words (with or without meaning) a...
- Consider the following statements : 1. If f is the subset of Z\times Z defined by f=\{(xy,x-y);x,y\in Z\}, then f is a function from...
- For how many quadratic equations, the sum of roots is equal to the product of roots?