Class 12 Exam  >  Class 12 Questions  >  What will be the equation of the normal to th... Start Learning for Free
 What will be the equation of the normal to the parabola y2 = 5x that makes an angle 45° with the x axis?
  • a)
    4(x – y) = 15
  • b)
    4(x + y) = 15
  • c)
    2(x – y) = 15
  • d)
    2(x + y) = 15
Correct answer is option 'A'. Can you explain this answer?
Most Upvoted Answer
What will be the equation of the normal to the parabola y2 = 5x that m...
The equation of the given parabola is, y2 = 5x ……….(1)
Differentiating both sides of (1) with respect to y, we get,
2y = 5(dx/dy)
Or dx/dy = 2y/5
Take any point P((5/4)t2, (5/2)t). Then, the normal to the curve (1) at P is,
-[dx/dy]P = -(2*5t/2)/5 = -t
By the question, slope of the normal to the curve (1) at P is tan45°.
Thus, -t = 1
Or t = -1
So, the required equation of normal is,
y – 5t/2 = -t(x – 5t2/4)
Simplifying further we get,
4(x – y) = 15
Free Test
Community Answer
What will be the equation of the normal to the parabola y2 = 5x that m...
To find the equation of the normal to the parabola, we need to determine the slope of the tangent line first. We can differentiate the equation of the parabola to find the slope at a given point:

y^2 = 5x

Differentiating implicitly, we get:

2yy' = 5

y' = 5/(2y)

Next, we need to find the coordinates of the point on the parabola where the tangent line is to be drawn. Let's assume this point is (a, b).

Substituting these coordinates into the equation of the parabola, we have:

b^2 = 5a

Now, we substitute the slope of the tangent line (y') and the coordinates of the point (a, b) into the point-slope form of a line:

y - b = (5/(2b))(x - a)

Since the angle between the tangent line and the normal line is 45 degrees, the slopes of the two lines are negative reciprocals of each other. Therefore, the slope of the normal line is -2/5.

Substitute this slope and the coordinates of the point (a, b) into the point-slope form:

y - b = (-2/5)(x - a)

Simplifying, we have:

5(y - b) = -2(x - a)

5y - 5b = -2x + 2a

Rearranging the equation, we get:

2x + 5y = 2a + 5b

Therefore, the equation of the normal to the parabola y^2 = 5x that makes an angle of 45 degrees is 2x + 5y = 2a + 5b.
Explore Courses for Class 12 exam

Top Courses for Class 12

Question Description
What will be the equation of the normal to the parabola y2 = 5x that makes an angle 45° with the x axis?a)4(x – y) = 15b)4(x + y) = 15c)2(x – y) = 15d)2(x + y) = 15Correct answer is option 'A'. Can you explain this answer? for Class 12 2025 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about What will be the equation of the normal to the parabola y2 = 5x that makes an angle 45° with the x axis?a)4(x – y) = 15b)4(x + y) = 15c)2(x – y) = 15d)2(x + y) = 15Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for Class 12 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for What will be the equation of the normal to the parabola y2 = 5x that makes an angle 45° with the x axis?a)4(x – y) = 15b)4(x + y) = 15c)2(x – y) = 15d)2(x + y) = 15Correct answer is option 'A'. Can you explain this answer?.
Solutions for What will be the equation of the normal to the parabola y2 = 5x that makes an angle 45° with the x axis?a)4(x – y) = 15b)4(x + y) = 15c)2(x – y) = 15d)2(x + y) = 15Correct answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 12. Download more important topics, notes, lectures and mock test series for Class 12 Exam by signing up for free.
Here you can find the meaning of What will be the equation of the normal to the parabola y2 = 5x that makes an angle 45° with the x axis?a)4(x – y) = 15b)4(x + y) = 15c)2(x – y) = 15d)2(x + y) = 15Correct answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of What will be the equation of the normal to the parabola y2 = 5x that makes an angle 45° with the x axis?a)4(x – y) = 15b)4(x + y) = 15c)2(x – y) = 15d)2(x + y) = 15Correct answer is option 'A'. Can you explain this answer?, a detailed solution for What will be the equation of the normal to the parabola y2 = 5x that makes an angle 45° with the x axis?a)4(x – y) = 15b)4(x + y) = 15c)2(x – y) = 15d)2(x + y) = 15Correct answer is option 'A'. Can you explain this answer? has been provided alongside types of What will be the equation of the normal to the parabola y2 = 5x that makes an angle 45° with the x axis?a)4(x – y) = 15b)4(x + y) = 15c)2(x – y) = 15d)2(x + y) = 15Correct answer is option 'A'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice What will be the equation of the normal to the parabola y2 = 5x that makes an angle 45° with the x axis?a)4(x – y) = 15b)4(x + y) = 15c)2(x – y) = 15d)2(x + y) = 15Correct answer is option 'A'. Can you explain this answer? tests, examples and also practice Class 12 tests.
Explore Courses for Class 12 exam

Top Courses for Class 12

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