How many real solutions does have?
Answer and explanation
Correct answer: E.
- Step 1: Square both sides: , so and or .
- Step 2: Squaring can introduce false solutions. Check: gives , which works; gives , which fails.
- Step 3: There is exactly solution.
Answer
.
Why not the others: counts the false solution ; rejects both; and exceed the number of roots of a quadratic.
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