lpx88 SG When u encounter a qn like.. sin x = -1/2 Do u leave out the minus sign when keying it in the calculator to find the basic angle?
lpx88 SG Ok but in the later part we must identify it to be in the 3rd and 4th quadrant because it is sin negative?
lpx88 SG Alright... K i reached this part alrdy.. 2x=210 degrees,330 degrees So i must add 360 degrees to each angle and then divide by two to get the 4 final answers?
tut4nkh4m3n SG just divide by two i thought? i'm not too gd with trigo too. but if you alr know 2x is 210 and 330, and you wana find x, isn't it just dividing by two?
Y_Shun SG you must see the 4 quardrants ma sine negative... 3rd and 4th quardant 180 + basic angle / 2 360 - basic angle / 2 get the ans lohs
omgukilledkenny SG er..i think you still gotta add 360 because its a double angle or something like that? i havent touched trigo for a year.
lpx88 SG No....that step is incomplete i think... Cause If x is 0 So i think must add until 720 degrees...then can divide by two... Haha my trio like abit rusty also..so anything a bit unsure just clarify here lor...
lpx88 SG hese are the topics im damn strong in PnC and identities are either u see it or u don though...jus practise alot..esp for PnC..so u know when to P and when to C Im in a tight situation with trigo differentiation though =/
tut4nkh4m3n SG yeah okay which means just keep adding rounds and dividing by two right? either way your final ans should be btwn 0 and 390 degrees right? it's just how many ans you have right?
