Leaving Cert Higher Level Maths 2020 Paper 1 Question 4

Question 4 from the leaving cert higher level maths 2020 paper 1 is a differentiation calculus question. We start by finding the first derivative of a cubic function with an unknown coefficient, then we are asked to find the turning points (local max and local min) and to show that a second function passes through these points. This also brings in coordinate geometry in the form of equation of a line and slope. Finally we are asked to find the point of inflection of the cubic function and again show that this point is also on the linear suction.

[@tammymcinerney1486]

I love u sm for taking the time to teach this to ppl

[@seanmorrissy7347]

Buzzing, I got them all right alone, cheers

[@seanmorrissy7347]

I did part (c) by getting the midpoint of g(x) and subbing into f(x) though, anyone know if that’s ok?

[@SimpleScienceandMaths]

Solutions to each question: Question 1: kzbin.info/www/bejne/o3u7aWmdaqh5i6M Question 2: kzbin.info/www/bejne/n3TWaIF-ppKfY7s Question 3: kzbin.info/www/bejne/h2api5Wfeq2hnsU Question 4: kzbin.info/www/bejne/foXZnqqGn96rbZo Question 5: kzbin.info/www/bejne/eHaUo2Zul7mtaac Question 6: kzbin.info/www/bejne/qqe1c3iCo8adqdk Question 7: kzbin.info/www/bejne/n5bXZ2huh7qFaqs Question 8: kzbin.info/www/bejne/aYaYYaGhnJuKr8k Question 9: kzbin.info/www/bejne/fXOaf6aEhsaVrMU

[@ChloE123omega]

Thank you so much 🙏🏾

[@handicappedjihadist5833]

6:07: concerning slope formula, how might one decide whether coordinates 5 and 1 are x1 and x2, respectively? If I got point (1,15) as my initial answer, I assume I would incorrectly mark 1 as x1.