Check sibling questions

Slide15.JPG

Slide16.JPG

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


Transcript

Ex 8.3, 4 (a) (a) Simplify 3x (4x – 5) + 3 and find its values for (i) x = 3 (ii) x = 1/23𝑥 (4𝑥−5)+3 = (3𝑥×4𝑥)−(3𝑥×5)+3 = 𝟏𝟐𝒙^𝟐−𝟏𝟓𝒙+𝟑 (i) For 𝒙=𝟑 Putting 𝑥=3 in expression 12𝑥^2−15𝑥+3 = 12(3)^2−15(3)+3 = (𝟏𝟐 × 𝟗)−(𝟏𝟓 × 𝟑) +𝟑 = 108−45 +3 = 108−42 = 𝟔𝟔 (ii) For 𝒙=𝟏/𝟐 Putting 𝑥=1/2 in expression 12𝑥^2−15𝑥+3 = 12(1/2)^2−15(1/2)+3 = 𝟏𝟐(𝟏/𝟐×𝟏/𝟐)− 𝟏𝟓/𝟐 +𝟑 = 12×(1/4)−15/2+3 = 𝟑−𝟏𝟓/𝟐+𝟑 = 6−15/2 = (6 × 2 − 15)/2 = (12 − 15)/2 = (−𝟑)/𝟐

Ask a doubt
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 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.