Question 36 (iii) (B) - CBSE Class 12 Sample Paper for 2025 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

Last updated at August 14, 2026 by Teachoo

Question 36 (iii) (B) - Check whether V has a point of inflection at x - CBSE Class 12 Sample Paper for 2025 Boards

part 2 - Question 36 (iii) (B) - CBSE Class 12 Sample Paper for 2025 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12

part 3 - Question 36 (iii) (B) - CBSE Class 12 Sample Paper for 2025 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12

Next: Question 37 (i) [Case Based] → Remove Ads

Teachoo · Class 12 Explore Class 12

Transcript

Question 36 (iii) (B) Check whether V has a point of inflection at 𝑥=65/6 or not?Now, 𝐕(𝐱) = 2(2𝑥^3−65𝑥^2+500𝑥) 𝐕′(𝐱) = 4(𝑥−5)(3𝑥−50) 𝐕^′′ (𝐱) = 4 (6𝑥−65) Now, for point of inflection… it is not necessary for V’(x) to be zero But, V’’(x) = 0 is important And, Sign of V’’(x) on left and right of the point should change At 𝒙=𝟔𝟓/𝟔 𝑽^′′ (𝟔𝟓/𝟔) = 4 (6 ×65/6−65) = 4 (65−65) = 0 Now, Checking Sign of V’’(x) on left and right of 𝒙=𝟔𝟓/𝟔 Since V’’(65/6) = 0 And, Sign of V’’(x) on left and right of 𝑥=65/6 changes Thus, x = 𝟔𝟓/𝟔 is a point of inflection

Made by

Davneet Singh

Davneet Singh is an IIT Kanpur graduate and has been teaching for 16+ years. At Teachoo, he breaks down Maths, Science and Computer Science into simple steps so students understand concepts deeply and score with confidence.

Many students prefer Teachoo Black for a smooth, ad-free learning experience.

Class 6

Class 7

Class 8

Class 9

Class 10

Class 11

Class 12

Courses

Interesting

Popular