Question

Please help me with the following by checking it.

Solve for x: √(2x^2+5)=2

A. ±1

B. √2 - (This is my answer.)

C. ±2

D. None of the above.

I am not sure about my answer, can someone check it please. Any help will be greatly appreciated.:)

Answer 1

√(2x^2+5)=2
square both sides
2x^2 + 5 = 4
2x^2 = -1
x^2 = -1/2
no solution, since we cannot take the square root of a negative in the real number set.

Answer 2

Thank you Reiny, I now understand! :)