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Question : 2 of 100
Marks:
+1,
-0
Solution:
Let
√28−10√3=√x−√y ⇒
28−10√3=x+y−2√xy ⇒
x+y=28,xy=75 Therefore,
(x−y)2=(x+y)2−4xy=784−300=484 ⇒
xy=22 or
x=25,y=3 Thus,
√28−10√3=√25−√3 Again, let
√7+4√3=√p+√q ⇒
7+4√3=p+q+2√pq ⇒
p+q=7,pq=12 ⇒
p−q=1 or
p=4,q=3 Thus,
√7+4√3=√4+√3 Now,
(28−10√3)−(7+4√3)− =√25−√3−=√25−√3− =√25−√4=5−2=3
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