Nee help on fundamentals of Algebra

Question

I m stuck with few concepts
1. a^2 = b^2
>>>>Is a or b + or - ve

2. a = b^2

Either a = +b or a = -b 
Am i right or wrong

3. a^2 = b ^4

>>>.Which one is +or - ve

I have gone through various sources but i am getting confused over and again

Bunuel can u pls help...................

BrushMyQuant · Answer

Am not Bunuel but I can try

This means that a = +b or -b Do both a and b can be positive or negative or 0 In this b can be + or - but a will be + or 0 for sure as b^2 cannot be negative in any case Here both a and b can be positive negative or 0 as a= +b^2 or -b^2 Hope it helps!

gurpreetsingh · Answer

1. When  a^2 = b^2  and you want to take square root then the answer is

|a|=|b|  Now when you open the MOD the answer becomes  a = +- b

2. You are wrong. Apply the above rule and you would  \sqrt{a}= b 
b = positive because square root of value is always positive.

3. a^2 = b ^4.. Again apply the rule of 1. You will get  |a|=|b^2| 
Since  b^2  is always positive => a is always positive. Thus  a = b^2

Archit143 · Answer

Thnx all for clearing my doubt...

Nee help on fundamentals of Algebra

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