What is the integration of x^3/2x-1?
∫ x^3/2x+1 dx
= Divide and multiply in numerator by 8
= 1/8∫ [8x^3/(2x+1)]
= 1/8 ∫[( 8x^3+1–1) / (2x+1)]
= 1/8 ∫[(2x+1)(4x^2 - 2x +1) -1 / (2x+1)]
By using the formula : a^3 + b^3 = (a+b)(a^2+ b^2 -ab)
= 1/8 ∫[(2x+1)(4x^2 - 2x +1)dx /(2x+1) - 1/8 ∫ 1 dx/(2x+1)]
= 1/8 ∫[(4x^2 - 2x +1)dx - 1/8 ∫ 1 dx/(2x+1)]
= 1/8 ∫(4x^2)dx -1/8 ∫ 2x + 1/8 ∫dx - 1/8 ∫ 1 dx/(2x+1)]
= 1/8 ∫(4x^2)dx - 1/8 ∫ 2x + 1/8 ∫dx - 1/8 ∫ 1 dx/(2x+1)]
= 4/8 ∫(x^2)dx -2/8 ∫x dx + 1/8 ∫dx - 1/8 ∫ 1 dx/(2x+1)]
= 1/2 ∫(x^2) -1/4 ∫x dx + 1/8 ∫dx - 1/8 ∫ 1 dx/(2x+1)]
= Now integrating we get;
=x^3 /6 - x^/8 + x /8 - 1/8 ∫ 1 dx/(2x+1)
Now for this put 2x+1 = t…… …… (1) differentiate both sides we get,
2 dx = dt
Now,
= x^3 /6 - x^/8 + x /8 - 1/(8 x 2)∫ dt/t
= x^3 /6 - x^/8 + x /8 - 1/16∫ dt/t
= x^3 /6 - x^/8 + x /8 - 1/16 lnt
= x^3 /6 - x^/8 + x /8 - 1/16 ln (2x+1) { from (1)}
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What is the integration of x^3/2x-1?
Integration of x^(3/2)/(2x-1)
To find the integration of the given expression, we can use the method of substitution. Let's break down the process step by step:
Step 1: Identify the function
The given expression is x^(3/2)/(2x-1). We need to find its antiderivative or integral.
Step 2: Simplify the function
We can simplify the given expression by dividing the numerator and denominator by x^(1/2). This gives us:
(x^(3/2))/(2x-1) = (x^(3/2))/(2x^(1/2) - 1/x^(1/2))
Step 3: Perform substitution
Let's substitute u = x^(1/2). This implies that du/dx = (1/2)x^(-1/2). Rearranging, we get dx = 2u du.
Step 4: Rewrite the integral
Using the substitution, we can rewrite the integral as:
∫(x^(3/2))/(2x-1) dx = ∫(u^2)/(2u^2 - 1) * 2u du
Step 5: Simplify and solve the integral
Now, we can simplify the integral further:
∫(u^2)/(2u^2 - 1) * 2u du = ∫(2u^3)/(2u^2 - 1) du
Step 6: Divide the numerator by the denominator
To make it easier to integrate, let's divide the numerator (2u^3) by the denominator (2u^2 - 1):
∫(2u^3)/(2u^2 - 1) du = ∫(u^3 * 2)/(u^2 * 2 - 1) du
Step 7: Apply the power rule for integration
Now, we can apply the power rule for integration, which states that ∫x^n dx = (1/(n+1)) * x^(n+1) + C, where C is the constant of integration.
Using this rule, we integrate the simplified expression:
∫(u^3 * 2)/(u^2 * 2 - 1) du = 2∫(u^3)/(u^2 * 2 - 1) du
Step 8: Perform further simplification
We can simplify the denominator (u^2 * 2 - 1) by expanding it:
2∫(u^3)/(u^2 * 2 - 1) du = 2∫(u^3)/(2u^2 - 1) du
Step 9: Apply the power rule for integration again
We can now apply the power rule for integration to the simplified expression:
2∫(u^3)/(2u^2 - 1) du = 2*(1/4)∫(2u^2 - 1 + 1)/(2u^2 - 1) du
Step 10: Evaluate the integral
By applying the power rule for integration, we can