JEE Exam  >  JEE Questions  >  If g2+ f2= c, then the equation x2+ y2+ 2gx +... Start Learning for Free
If g+ f= c, then the equation x+ y+ 2gx + 2fy + c = 0 will represent
  • a)
    A circle of radius g
  • b)
    A circle of radius f
  • c)
    A circle of diameter √c
  • d)
    A circle of radius zero
Correct answer is option 'D'. Can you explain this answer?
Most Upvoted Answer
If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will represen...
Free Test
Community Answer
If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will represen...
Understanding the Equation of a Circle
The given equation is:
x² + y² + 2gx + 2fy + c = 0.
This can be rearranged to identify the properties of the circle.
Complete the Square
To convert this equation into a standard form, we can complete the square:
1. Rearranging:
- x² + 2gx + y² + 2fy = -c
2. Completing the square:
- (x + g)² - g² + (y + f)² - f² = -c
3. Simplifying:
- (x + g)² + (y + f)² = g² + f² - c
Analyzing the Circle's Properties
From the completed square form, we see that:
- The center of the circle is at (-g, -f).
- The radius squared (r²) is given by: r² = g² + f² - c.
Condition for Radius
Now, according to the problem statement:
g² + f² = c.
Substituting this into the radius formula gives:
r² = g² + f² - g² - f² = 0.
Thus, the radius r = √0 = 0.
Conclusion
Since the radius is zero, the equation represents a single point rather than a circle with a physical radius.
Therefore, the correct answer is:
Option D: A circle of radius zero.
This represents a degenerate circle, which is effectively a point in the plane.
Explore Courses for JEE exam
Question Description
If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will representa)A circle of radius gb)A circle of radius fc)A circle of diameter √cd)A circle of radius zeroCorrect answer is option 'D'. Can you explain this answer? for JEE 2025 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will representa)A circle of radius gb)A circle of radius fc)A circle of diameter √cd)A circle of radius zeroCorrect answer is option 'D'. Can you explain this answer? covers all topics & solutions for JEE 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will representa)A circle of radius gb)A circle of radius fc)A circle of diameter √cd)A circle of radius zeroCorrect answer is option 'D'. Can you explain this answer?.
Solutions for If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will representa)A circle of radius gb)A circle of radius fc)A circle of diameter √cd)A circle of radius zeroCorrect answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for JEE. Download more important topics, notes, lectures and mock test series for JEE Exam by signing up for free.
Here you can find the meaning of If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will representa)A circle of radius gb)A circle of radius fc)A circle of diameter √cd)A circle of radius zeroCorrect answer is option 'D'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will representa)A circle of radius gb)A circle of radius fc)A circle of diameter √cd)A circle of radius zeroCorrect answer is option 'D'. Can you explain this answer?, a detailed solution for If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will representa)A circle of radius gb)A circle of radius fc)A circle of diameter √cd)A circle of radius zeroCorrect answer is option 'D'. Can you explain this answer? has been provided alongside types of If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will representa)A circle of radius gb)A circle of radius fc)A circle of diameter √cd)A circle of radius zeroCorrect answer is option 'D'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice If g2+ f2= c, then the equation x2+ y2+ 2gx + 2fy + c = 0will representa)A circle of radius gb)A circle of radius fc)A circle of diameter √cd)A circle of radius zeroCorrect answer is option 'D'. Can you explain this answer? tests, examples and also practice JEE tests.
Explore Courses for JEE exam

Top Courses for JEE

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev