JEE Mains · Maths · STD 11 - 4.2 Quadratic equations and inequations
Let \([t]\) denote the greatest integer \(\leq t .\) Then the equation in \(x ,[ x ]^{2}+2[ x +2]-7=0\) has
- A no integral solution
- B exactly four integral solutions
- C exactly two solutions
- D infinitely many solutions
Answer & Solution
Correct Answer
(D) infinitely many solutions
Step-by-step Solution
Detailed explanation
\([x]^{2}+2[x+2]-7=0\) \(\Rightarrow[x]^{2}+2[x]+4-7=0\) \(\Rightarrow[x]=1,-3\) \(\Rightarrow x \in[1,2) \cup[-3,-2)\)
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