Solving the Equation: (2x^2-3x-1)^2-3(2x^2-3x-5)-16=0
This equation appears complex, but we can simplify it by using substitution and then applying the quadratic formula. Here's a step-by-step solution:
1. Substitution:
Let's make the equation easier to handle by substituting y = 2x^2 - 3x - 1.
This transforms our equation into:
y^2 - 3(y - 4) - 16 = 0
2. Simplifying the Equation:
Expanding and rearranging the terms, we get:
y^2 - 3y + 12 - 16 = 0
y^2 - 3y - 4 = 0
3. Solving the Quadratic Equation:
Now we have a simple quadratic equation. We can solve it using the quadratic formula:
y = (-b ± √(b^2 - 4ac)) / 2a
Where:
- a = 1
- b = -3
- c = -4
Plugging in these values:
y = (3 ± √((-3)^2 - 4 * 1 * -4)) / (2 * 1)
y = (3 ± √(25)) / 2
y = (3 ± 5) / 2
This gives us two possible solutions for y:
- y1 = 4
- y2 = -1
4. Back-substitution:
Now, let's substitute back the original expression for y:
For y1 = 4:
2x^2 - 3x - 1 = 4
2x^2 - 3x - 5 = 0
For y2 = -1:
2x^2 - 3x - 1 = -1
2x^2 - 3x = 0
5. Solving for x:
We now have two separate quadratic equations to solve for x. We can use the quadratic formula again or factor them directly:
For 2x^2 - 3x - 5 = 0:
- x1 = (3 + √49) / 4 = 2.5
- x2 = (3 - √49) / 4 = -1
For 2x^2 - 3x = 0:
- x3 = 0
- x4 = 3/2
6. Final Solutions:
Therefore, the solutions to the original equation (2x^2-3x-1)^2-3(2x^2-3x-5)-16=0 are:
- x = 2.5
- x = -1
- x = 0
- x = 3/2