Learn in your speed, with individual attention - Teachoo Maths 1-on-1 Class

Ex 4.3

Question 1 (i)
Deleted for CBSE Board 2024 Exams

Question 1 (ii) Important Deleted for CBSE Board 2024 Exams

Question 1 (iii) Deleted for CBSE Board 2024 Exams

Question 1 (iv) Important Deleted for CBSE Board 2024 Exams You are here

Question 2 (i)

Question 2 (ii)

Question 2 (iii)

Question 2 (iv) Important

Question 3 (i) Important

Question 3 (ii)

Question 4

Question 5

Question 6

Question 7 Important

Question 8 Important

Question 9 Important

Question 10 Important

Question 11

Last updated at May 29, 2023 by Teachoo

Ex 4.3 ,1 Find the roots of the following quadratic equations, if they exist, by the method of completing the square: (iv) 2x2 + x + 4 = 0 2x2 + x + 4 = 0 Dividing equation by 2 (2𝑥2 + 𝑥 + 4)/2=0/2 2𝑥2/2+𝑥/2 + 4/2=0 x2 + 𝑥/2+2=0 We know that (a + b)2 = a2 + 2ab + b2 Here, a = x & 2ab = 𝑥/2 2xb = 𝑥/2 2b = 1/2 b = 1/2×1/2 b = 1/4 Now, in our equation x2 + 𝑥/2+2=0 Adding and subtracting (1/4)^2 x2 + 𝑥/2 +2+(1/4)^2−(1/4)^2=0 "x2 + " 𝑥/2+(1/4)^2+2−(1/4)^2=0 (𝑥+1/4)^2+2−(1/4)^2=0 (𝑥+1/4)^2+2−1/16=0 (𝑥+1/4)^2+((32 − 1)/16)=0 (𝑥+1/4)^2+ 31/16=0 (𝑥+1/4)^2=(−31)/16 Since square of any number cannot be negative So, answer does not exist