Find the derivative of the function f(x)=2x2+3x−5f(x)=2 x^{2}+3 x-5 at x=−1x=-1. Also prove that f′(0)+3f′(−1)=0f^{\prime}(0)+3 f^{\prime}(-1)=0.

Answer: The derivative of the function f(x)=2x2+3x−5f(x)=2 x^{2}+3 x-5 at x=−1x=-1 is −1-1. The relation f′(0)+3f′(−1)=0f^{\prime}(0)+3 f^{\prime}(-1)=0 is proven.

Step-by-step solution

Step 1: Find the general derivative of f(x)f(x)

To find the derivative of the function f(x)=2x2+3x−5f(x) = 2x^2 + 3x - 5, we apply the power rule and the constant multiple rule of differentiation. The derivative of 2x22x^2 is 4x4x, the derivative of 3x3x is 33, and the derivative of a constant −5-5 is 00.

Step 2: Evaluate f′(−1)f'(-1)

Now we substitute x=−1x = -1 into the derivative function f′(x)=4x+3f'(x) = 4x + 3 to find the derivative at that specific point.

Step 3: Evaluate f′(0)f'(0)

Similarly, we substitute x=0x = 0 into the derivative function f′(x)=4x+3f'(x) = 4x + 3 to find the derivative at x=0x=0.

Step 4: Prove the given relation

Finally, we substitute the calculated values of f′(0)f'(0) and f′(−1)f'(-1) into the given relation f′(0)+3f′(−1)f'(0) + 3f'(-1) to verify if it equals zero.

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