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Question : 29 of 120
Marks:
+1,
-0
Solution:
Given, |a−b|=√7
⇒|a−b|2‌‌=7
⇒(a−b)⋅(a−b)‌‌=7
⇒|a|2−2a⋅b+|b|2‌‌=7
⇒9−2a⋅b+16‌‌=7
⇒25−2a⋅b‌‌=7
⇒2a⋅b‌‌=18
⇒a⋅b‌‌=9
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