To show increasing/decreasing in whole domain
To show increasing/decreasing in whole domain
Last updated at August 2, 2026 by Teachoo
Transcript
Ex 6.2, 18 Prove that the function given by f (š„) = š„3 ā 3š„2 + 3š„ ā 100 is increasing in R. We need to show f(š„) is strictly increasing on R i.e. we need to show fā(š) > 0 Finding fā(š) fā(š„)= 3x2 ā 6x + 3 ā 0 = 3(š„2ā2š„+1) = 3((š„)2+(1)2ā2(š„)(1)) = 3(š„ā1)2 Since Square of any number is always positive (š„ā1)2 > 0 3(š„ā1)2>0 fā(š) > 0 Hence, fā(š„) > 0 for all values of š„ ā“ f(š„) is strictly increasing on R