F5C3
When find the area of shaded region , you can choose to do integration with respect to x-axis or y-axis .

F5C4
Who drop this chapter raise up your hand 🙋 .
That is no such rule that " C " and " P " cannot be use simultaneously in the step .
If forming a code , the code can start with digit ' 0 ' , however if forming a number then the number cannot start with digit ' 0 ' .

F5C5
If you represent the probability distribution for binomail distribution with graph , then the graph shape is either ( from left to right )
(a)upward then downward
(b)upward only
(c)downward only

For normal distribution , always sketch the graph to get a clearly visualization especially when want to find the z-score . If the value of the probability is more than 0.5 , then the region under the graph that represent the probability is MUST at both side of the f(z)-axis . However , if the value of the probability is less than 0.5 , the region under the graph that represent the probability is either at one side or both side of the f(z)-axis , it depend to the question .

Extra : Yes you can directly get the z-score from your calculator if the probability is given , but it will not give you any working step marks 🫡

F5C6
Again , who drop this chapter raise up your hand 🙋‍♂
For proving trigo identities , always start with side which is more complicated , priority to the side that has addition formulae while other side dont have .

Always draw a right-angle triangle no matter the angle lies at which quadrant so you can see clearly the length and the sign of the side of the triangle .

When solving trigo equations , always find the reference ( basic ) angle first no matter the sign of the value . Then find the corresponding angle at suitable quadrant according to the sign of the value .

F5C7
The objective function k = ax + by , the value of k can assume as any positive value , must take as common multiple of a and b is just for convenient . Value of k will not affect the gradient of the line that represent the objective function .

F5C8
The formula distance travelled at n-th second :
S(n-th) = l S(n) - S(n-1) l
This formula is only valid IF AND ONLY IF the particle didnt stop momentary / change direction of movement between the duration (n-1)th second to n-th second .

This is the analysis question ( without paper 2 Section C ) for Selangor Add Math trial from 2021 to 2023
Note : This is just for reference , if you think want to skip certain chapter for certain paper that is your own RISK , since trial paper doesnt follow the " common " way , example : System of Equation at paper 1 , or Solutions of Triangle at Paper 1 Section B 2021 🤣 .
Tomorrow has add math paper for Selangor , good luck 🫡