polarsnake SG Well some of my friends were arguing over -2^2= -4 or =4. Well what do you think? Most importantly, would the teacher mark it wrong or right? I asked my teacher this very same queation and i stumped him for a while
hisoka SG anything squared except for i is positive however, if the notation is as you have typed then the answer is -4 reason being the - is not included in the ^2
polarsnake SG Yea, but when there is no bracket available it becomes quite confusing and misleading hehe...
polarsnake SG In my Homework I always encounter this kind of problem, I put answer as 4, my teacher mark correct Now, what would the teacher think if I had put -4 instead? Would he mark it as wrong? I wonder...
oxford mushroom SG You have a point there...can argue your case if your teacher mark you wrong. Good practice if you intend to take up law in future
FadeToBlack SG yes, because generally - ( minus ) belongs to the 2 If there is no bracket stated, obviously it meant -2 and not -(2). therefore, answer should be positive 4.
CoolMyth SG Riddle me this: Consider the case (-2)^2 = 4 What if we "power" both sides by 1/2, ie: (-2)^[2 * (1/2)] = 4^(1/2) --> (-2)^1 = 4^(1/2) --> (-2)^1 = sqrt (4) --> - 2 = 2 Where is the contradiction?
kenshin_himura SG (-2)^1 = sqrt (4) when u root 4 u get +2 or -2 there for there r 2 ans =D both are real roots jsut that one is positive and one is negative root lor.
kenshin_himura SG and un forget when u apply 1/2 to both sides u get +2 and -2 on the other side therefore its tellies so no mistake
kenshin_himura SG actually i have a QS for all if X2 = 49 then sqrt of X2 will be +7 and -& but on the left will u get +x and -X. though it is wrong to write it this way i was wondering y?
Now,
what would the teacher think if I had put -4 instead? Would he mark
it as wrong? I wonder...
