Q. Given the function f(x)=2x−3x3−2, find f′(x) in simplified form.Answer: f′(x)=
Quotient Rule Explanation: To find the derivative of the function f(x)=2x−3x3−2, we will use the quotient rule. The quotient rule states that if we have a function that is the quotient of two functions, v(x)u(x), then its derivative f′(x) is given by (v(x))2v(x)⋅u′(x)−u(x)⋅v′(x). Here, u(x)=x3−2 and v(x)=2x−3.
Derivative of u(x): First, we need to find the derivative of u(x)=x3−2. The derivative of x3 is 3x2, and the derivative of a constant is 0. Therefore, u′(x)=3x2.
Derivative of v(x): Next, we need to find the derivative of v(x)=2x−3. The derivative of 2x is 2, and the derivative of a constant is 0. Therefore, v′(x)=2.
Applying Quotient Rule: Now we apply the quotient rule. We have u′(x)=3x2 and v′(x)=2, so we plug these into the quotient rule formula:f′(x)=(2x−3)2(2x−3)∗(3x2)−(x3−2)∗(2).Let's simplify this expression step by step.
Multiplying (2x−3) by 3x2: First, we multiply (2x−3) by 3x2 to get 6x3−9x2.
Multiplying (x3−2) by 2: Next, we multiply (x3−2) by 2 to get 2x3−4.
Subtracting Products: Now we subtract the second product from the first product to get the numerator of the derivative:(6x3−9x2)−(2x3−4)=6x3−9x2−2x3+4.
Combining Like Terms: Simplify the numerator by combining like terms:6x3−2x3−9x2+4=4x3−9x2+4.
Final Derivative: Now we have the simplified numerator, and we place it over the square of the denominator:f′(x)=(2x−3)24x3−9x2+4.This is the derivative of the function in simplified form.
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