Solve each of the equation in Exercises 6 to 9:  21x² – 28x + 10 = 0

Solution:

The given quadratic equation can be written as,

21x² – 28x + 10 = 0

By comparing this with ax² + bx + c = 0, we get a = 21, b = -28, and c = 10.

Its discriminant is, D = b² - 4ac = (-28)² - 4(21)(10) = -56

The solutions of the given quadratic equation are,

(- b ± √D)/2a = 28 ± √(-56) ) / 2(21)

= (28 ± i√56) / 42 [∵ √- 1 = i]

= (28 ± 2i√14) / 42

= 2/3 ± (√14/21) i

Hene the solutions of the given equation are x = 2/3 + i√14/ 21, 2/3 - i√ 14 / 21

NCERT Solutions Class 11 Maths Chapter 5 Exercise ME Question 9

Solve each of the equation in Exercises 6 to 9:  21x² – 28x + 10 = 0

Summary:

The solutions of 21x² – 28x + 10 = 0 are x = 2/3 + i√14 / 21, 2/3 - i√ 14/ 21