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Solve the equation by identifying the quadratic form. Use a substitute variable(t) and find all real solutions by factoring. Type your answers from smallest to largest. If an answer is not an integer then type it as a decimal rounded to the nearest hundredth. When typing exponents do not use spaces and use the carrot key ^ (press shift and 6). For example, x cubed can be typed as x^3.(x^2-1)^2+(x^2-1)-12=0Step 1. Identify the quadratic formLet t= Answer. We now have:t^2+t-12=0Step 2. FactorFactor this and solve for t to get t=Answerand Answer Step 3. Solve for xWe have solved for t now we need to use this value for t to help us solve for x. Revisit step 1 to remind you of the relationship between t and x. Type your real solutions (no extraneous) from smallest to largest.x= Answer and Answer

Solve the equation by identifying the quadratic form. Use a substitute variable(t-example-1
User Dibi
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1 Answer

5 votes

We have the following equation


\mleft(x^2-1\mright)^2+\mleft(x^2-1\mright)-12=0

Step 1.

Let t = (x^2 -1)


t=(x^2-1)

We now have:


t^2+t-12=0

Step 2. factor the above, to get t = -4 and 3


\begin{gathered} t^2+t-12=0 \\ t_(1,\: 2)=(-1\pm√(1^2-4\cdot\:1\cdot\left(-12\right)))/(2\cdot\:1) \\ t_(1,\: 2)=(-1\pm√(1^2-4\cdot\:1\cdot\left(-12\right)))/(2\cdot\:1) \\ t_1=(-1+7)/(2\cdot\:1),\: t_2=(-1-7)/(2\cdot\:1) \\ t_1=3,\: t_2=-4 \end{gathered}

Step 3.


\begin{gathered} t=(x^2-1) \\ t_1=3,\: t_2=-4 \end{gathered}

we can't use t = -4 because we will obtain an imaginary number, instead, lets use t=3 to solve for x


\begin{gathered} \mleft(x^2-1\mright)^{}=3 \\ x^2-1=3 \\ x^2-1+1=3+1 \\ x^2=4 \\ x=2,\: x=-2 \end{gathered}

So, x = -2 and 2

User Gngrwzrd
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