Check sibling questions

Misc 6 - Solve 3x2 - 4x + 20/3 = 0 - Chapter 5 NCERT - Quadaratic equation

Misc 6 - Chapter 5 Class 11 Complex Numbers - Part 2

This video is only available for Teachoo black users

Get Real time Doubt solving from 8pm to 12 am!


Transcript

Misc 6 Solve the equation 3π‘₯2 – 4π‘₯ + 20/3 = 0 3π‘₯2 – 4π‘₯ + 20/3 = 0 Multiplying both sides by 3 3 Γ— (3π‘₯2 – 4π‘₯ "+ " 20/3) = 3 Γ— 0 3 Γ— 3x2 – 3 Γ— 4x + 3 Γ— 20/3 = 0 9π‘₯2 – 12π‘₯ + 20 = 0 The above equation is of the form π‘Žπ‘₯2 + 𝑏π‘₯ + 𝑐 = 0 Where a = 9, b = –12, and c = 20 x = (βˆ’π‘Β±βˆš( 𝑏^2 βˆ’4π‘Žπ‘ ))/2π‘Ž = (βˆ’(βˆ’12) Β± √((βˆ’12)^2 βˆ’ 4 Γ— 9 Γ— 20))/(2 Γ— 9) = (12 Β± √(144 βˆ’720))/18 = (12 Β± √(βˆ’576))/18 = (12 Β± √(βˆ’1 Γ— 576))/18 = (12 Β± √(βˆ’1 ) Γ— √( 576))/18 = (12 Β± 𝑖 Γ— √( 576))/18 = (12 Β± 𝑖 Γ— √( 242))/18 = (12 Β± 𝑖 Γ— 24)/18 = (6(2 Β± 𝑖 Γ— 4))/18 = ((2 Β± 𝑖 Γ— 4))/3 = ((2 Β± 𝑖4))/3 Thus, π‘₯ = ((2 Β± 𝑖4))/3

Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.