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For which values of a will f(x)=0 .....have non real values

For which values of a will f(x)=0 .....have non real values-example-1
User Ziya ERKOC
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1 Answer

15 votes
15 votes

Step 1:

Write the function


f(x)=-2x^2\text{ + 4ax + 3}

Step 2:

From a quadratic formula

A negative discriminant indicates that neither of the solutions are real numbers.


\begin{gathered} \text{Discriminant D = b}^2\text{ - 4ac} \\ \end{gathered}

Step 3

for non real values , D < 0


b^2\text{ - 4ac < 0}

Step 4:

From the general equation of the quadratic equation


\begin{gathered} ax^2\text{ + bx + c = 0} \\ a\text{ = -2} \\ b\text{ = 4a} \\ c\text{ = 3} \end{gathered}

Step 5:


\begin{gathered} b^2\text{ - 4ac < 0} \\ (4a)^2\text{ - 4(-2)(3) < 0} \\ 16a^2\text{ + 24 < 0} \\ 16a^2\text{ < -}24 \\ a^2\text{ < }(-24)/(16) \\ a^2\text{ < }(-3)/(2) \\ a\text{ <}\pm\text{ }\sqrt[]{(-3)/(2)} \\ a\text{ < i}\sqrt[]{(3)/(2)\text{ }}\text{ or a < -}\sqrt[]{(3)/(2)} \end{gathered}

Final answer

False

User Robot Mess
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