Physics Wallah

Kerala Plus Two Chapter 5 Maths important Questions

Kerala Plus Two Chapter 5 covers limits, continuity, and differentiability of functions. Key topics include the Chain Rule, implicit differentiation, logarithmic derivatives, and second-order derivatives. Mastering these foundational calculus topics is important for scoring high in the Higher Secondary exams.
authorImageAmit Kumar Singh24 Oct, 2026
Kerala Plus Two Maths Chapter 5

 

Chapter 5 of Kerala Plus Two Maths covers continuity and differentiability, two core calculus topics. Questions usually ask students to check continuity at a given point, find an unknown constant, and differentiate trigonometric, inverse trigonometric, implicit, logarithmic, or parametric functions. 

Practising Kerala Plus Two Chapter 5 Maths important questions builds strong analytical skills and improves speed and accuracy. Solving them step by step also helps you manage your time better, so check the Kerala Plus Two timetable and plan your revision around your Maths exam date.

Kerala Plus Two Maths Chapter 5 Important Questions

Here are some important practice questions on Continuity and Differentiability for Kerala Plus Two Maths Chapter 5. Solve each question step by step to improve accuracy and strengthen your preparation. For better exam planning, check the Kerala Plus Two Maths exam pattern and timetable.

Question 1: Let f : R → R be defined by

f(x) = kx + 1, if x ≤ π
f(x) = cos x, if x > π

For what value of k is f continuous?

Answer:
For f(x) to be continuous at x = π, the left-hand limit, the right-hand limit and the value of the function must be equal.

Left-hand limit: lim (x→π⁻) f(x) = lim (x→π⁻) (kx + 1) = kπ + 1

Right-hand limit: lim (x→π⁺) f(x) = lim (x→π⁺) cos x = cos π = −1

Value of the function: f(π) = kπ + 1

Equating the left-hand and right-hand limits:
kπ + 1 = −1
kπ = −2
k = −2/π

Question 2: Discuss the continuity of the function

f(x) = 3x + 1, if x ≤ 3
f(x) = x² + 1, if x > 3

at x = 3.

Answer:
Left-hand limit: lim (x→3⁻) f(x) = lim (x→3⁻) (3x + 1) = 3(3) + 1 = 10

Right-hand limit: lim (x→3⁺) f(x) = lim (x→3⁺) (x² + 1) = 3² + 1 = 10

Value of the function: f(3) = 3(3) + 1 = 10

Since lim (x→3⁻) f(x) = lim (x→3⁺) f(x) = f(3) = 10, the function f(x) is continuous at x = 3.

Question 3: Find dy/dx, if x² + y² + xy = 100.

Answer:
Differentiating both sides with respect to x:

d/dx (x²) + d/dx (y²) + d/dx (xy) = d/dx (100)

2x + 2y (dy/dx) + [x (dy/dx) + y] = 0

(x + 2y) (dy/dx) = −(2x + y)

dy/dx = −(2x + y) / (x + 2y)

Note: These are only a few of the important questions from this chapter. For more practice questions on continuity and differentiability, download the PDF below.

Kerala Board Class 12 Maths Chapter 5 PDF Download

Students can download the Kerala Board Class 12 Maths Chapter 5 PDF for extra practice. The Kerala Class 12 Mathematics Continuity PDF includes questions on continuity, finding unknown constants, and implicit, logarithmic, parametric and second-order differentiation, so you can practise offline. 

Use the link below to get the PDF: 

Download Kerala Plus Two Maths Chapter 5 PDF

Study without using the internet

How Can You Use Kerala Plus Two Maths Chapter 5 Important Questions for Exam Preparation?

Solving practice questions in an organised way makes calculus revision easier. Before you start, check the Kerala Class 12 syllabus so you know which topics to cover. Then follow these steps to prepare well for your board exams:

  • Review Core Definitions: Learn the exact conditions for continuity and differentiability before attempting problems. Also revise the Kerala Plus Two Maths Inverse Trigonometric Functions MIQs, as inverse trigonometric functions often appear in differentiation questions.

  • Practice Step-by-Step Methods: Write down every intermediate step when solving derivative questions to secure full method marks.

  • Identify Weak Areas: Note down topics where errors occur, such as logarithmic differentiation or parametric forms, and re-solve them.

  • Time Your Practice: Solve questions under timed conditions using Kerala Plus Two model papers to build exam-day confidence.

Practising Kerala Plus Two Chapter 5 Maths important questions helps you understand continuity and differentiability concepts and improve problem-solving skills. Revise the solutions and practise the PDF questions to prepare for your board exams.

 

FAQs

Q1. What is the condition for a function to be continuous at a point?

A function f(x) is continuous at x = c if lim (x→c) f(x) = f(c). This means the left-hand limit, the right-hand limit and the value of the function at c must all be equal.

Q2. Are all continuous functions differentiable?

No, continuity does not guarantee differentiability. A function can be continuous at a point but fail to have a derivative if it has a sharp corner, such as f(x) = |x| at x = 0. However, every differentiable function is continuous.

Q3. Where can I download the Kerala Plus Two Maths Chapter 5 PDF?

You can download the Kerala Plus Two Maths Chapter 5 Continuity PDF from this page. It gives you extra practice questions on continuity and differentiability for offline study.

Q4. Which topics are covered in the Kerala Board Maths Class 12 Continuity PDF?

The PDF includes questions on continuity at a point, finding unknown constants for a continuous function, and the greatest integer function. It also covers differentiation of trigonometric, inverse trigonometric, implicit, logarithmic and parametric functions, and second-order derivatives.

Q5. How do you find the value of k for which a function is continuous at a point?

Find the left-hand limit and the right-hand limit at the given point, and equate both to the value of the function there. Then solve the resulting equation for k. For example, if f(x) = kx + 1 for x ≤ π and f(x) = cos x for x > π, then kπ + 1 = −1 gives k = −2/π.
Join 15 Million students on the app today!
Point IconLive & recorded classes available at ease
Point IconDashboard for progress tracking
Point IconLakhs of practice questions
Download ButtonDownload Button
Banner Image
Banner Image
Free Learning Resources
Know about Physics Wallah
Physics Wallah is an Indian edtech platform that provides accessible & comprehensive learning experiences to students from Class 6th to postgraduate level. We also provide extensive NCERT solutions, sample paper, NEET, JEE Mains, BITSAT previous year papers & more such resources to students. Physics Wallah also caters to over 3.5 million registered students and over 78 lakh+ Youtube subscribers with 4.8 rating on its app.
We Stand Out because
We provide students with intensive courses with India’s qualified & experienced faculties & mentors. PW strives to make the learning experience comprehensive and accessible for students of all sections of society. We believe in empowering every single student who couldn't dream of a good career in engineering and medical field earlier.
Our Key Focus Areas
Physics Wallah's main focus is to make the learning experience as economical as possible for all students. With our affordable courses like Lakshya, Udaan and Arjuna and many others, we have been able to provide a platform for lakhs of aspirants. From providing Chemistry, Maths, Physics formula to giving e-books of eminent authors like RD Sharma, RS Aggarwal and Lakhmir Singh, PW focuses on every single student's need for preparation.
What Makes Us Different
Physics Wallah strives to develop a comprehensive pedagogical structure for students, where they get a state-of-the-art learning experience with study material and resources. Apart from catering students preparing for JEE Mains and NEET, PW also provides study material for each state board like Uttar Pradesh, Bihar, and others

Copyright © 2026 Physicswallah Limited All rights reserved.