2:41 This question is very weird. It's asking you about a multiple choice test offering the following four options. But the question itself is a multiple choice test with four options. And it's kind of like a question inception 😂
At 8:11 you mention that f''(x)>0 for convex graphs, but I thought that was for concave graphs such as x^2! It even looks like you've graphed a concave graph too... I'm taking the TMUA on Tuesday so just checking! Thanks and your'e channel is great! :)
Yes x^2 is concave up. Which is the same as convex. Concave down is concave. I'm not sure why the difference in language used. You don't need the words though. Just have in your head the graph y=x^2. You know this would be overestimated by trapeziums, and you know f`` = 2 > 0. Therefore overestimates are when f``> 0 and under must be when f``< 0. You can just run through that process in your head rather than trying to remember the words and definitions
2:41 This question is very weird. It's asking you about a multiple choice test offering the following four options. But the question itself is a multiple choice test with four options. And it's kind of like a question inception 😂
contrapositives would be useful for question 20 on 2020 P2
smarrtttrtrt
At 8:11 you mention that f''(x)>0 for convex graphs, but I thought that was for concave graphs such as x^2! It even looks like you've graphed a concave graph too... I'm taking the TMUA on Tuesday so just checking! Thanks and your'e channel is great! :)
X^2 is a convex graph. I was told to remember it with ex being like an exponential
So x^2 isn’t concave upward? Thank yous so much!
Yes x^2 is concave up. Which is the same as convex. Concave down is concave. I'm not sure why the difference in language used.
You don't need the words though. Just have in your head the graph y=x^2. You know this would be overestimated by trapeziums, and you know f`` = 2 > 0. Therefore overestimates are when f``> 0 and under must be when f``< 0. You can just run through that process in your head rather than trying to remember the words and definitions