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Determine the values of a and b which would result in the function f(x) being differentiable at x = -5.

{ 3ax+5 for x < -5
f(x) = { bx²+x-2 for x ≥ ≥-5

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To determine the values of a and b which would result in the function f(x) being differentiable at x = -5, we need to find the values of a and b such that the two parts of the function are continuous and have the same derivative at x = -5. This requires setting the derivatives equal to each other and solving a system of equations for a and b.

To determine the values of a and b which would result in the function f(x) being differentiable at x = -5, we need to find the values of a and b such that the two parts of the function are continuous and have the same derivative at x = -5.

First, let's find the derivative of each part of the function:

For the first part when x < -5:

f'(x) = 3a

For the second part when x ≥ -5:

f'(x) = 2bx + 1

Next, we set the two derivatives equal to each other and solve for a and b:

3a = 2(-5)b + 1

3a = -10b + 1

Now we have one equation with two unknowns.

To solve for a and b, we need another equation.

Since the function is differentiable at x = -5, the two parts of the function must also be continuous at x = -5.

So, we set the two parts of the function equal to each other at x = -5:

3a(-5) + 5 = b(-5)^2 + (-5) - 2

-15a + 5 = 25b - 5 - 2

-15a + 5 = 25b - 7

Now we have a system of equations:

3a = -10b + 1

-15a + 5 = 25b - 7

We can solve this system of equations to find the values of a and b that satisfy both equations.

Once we find the values of a and b, we can substitute them back into the original function to confirm that it is differentiable at x = -5.

User Kathe
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