simplifying square roots
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(1+ root 3)^2 = 1+3+ (2 root 3)
= 4 + 2 root3
= 2( 2+root 3)
=> 1 + root 3 = (root 2) ( root( 2+ root 3)) ...
Substitute this value of (1 + root3) in the above expression
we get,
(root 2) ( root(2+ root3))*( root(2- root 3)) = (root 2) (root( 4-3))
{ using (a-b)(a+b) = (a^2 - b^2) }
So answer= (root 2)
Now, can we have the OA please :roll:
= 4 + 2 root3
= 2( 2+root 3)
=> 1 + root 3 = (root 2) ( root( 2+ root 3)) ...
Substitute this value of (1 + root3) in the above expression
we get,
(root 2) ( root(2+ root3))*( root(2- root 3)) = (root 2) (root( 4-3))
{ using (a-b)(a+b) = (a^2 - b^2) }
So answer= (root 2)
Now, can we have the OA please :roll:
MS
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square the whole expression - thats it.
we get (after squaring)
(1+3+2√3) (2-√3) = 2
so answer is √2
we get (after squaring)
(1+3+2√3) (2-√3) = 2
so answer is √2
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one, OA is "official answer".GambitOS wrote:OA is 2.
a. (1+root3)=(root1+root3)=(root4)=2
b. (root(2-root3))=(root(root4-root3)=(root1)=1
So 2*1=2
so when you give your answer don't say that it's the OA until you are sure that it's the OA
now,
(root1+root3)=(root4)=2--Wrong
(root1 + root3) is not equal to root(1+3)
root(root4-root3)=(root1)=1--wrong
(root4-root3) is not equal to root(4-3)
The powers of two are bloody impolite!!