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int (x+ ( cos^(-1)3x )^(2))/(sqrt(1-9x ^...

`int (x+ ( cos^(-1)3x )^(2))/(sqrt(1-9x ^(2)))dx = (1)/(k _(1)) ( sqrt(1-9x ^(2))+ (cos ^(-1) 3x )^(k_(2)))+c, ` then `k _(1) ^(2)+k_(2)^(2)=` (where C is an arbitrary constnat. )

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To solve the integral \[ I = \int \frac{x + (\cos^{-1}(3x))^2}{\sqrt{1 - 9x^2}} \, dx \] we will use substitution and integration techniques. ### Step 1: Substitution Let \( t = \cos^{-1}(3x) \). Then, differentiating both sides with respect to \( x \): \[ \frac{dt}{dx} = -\frac{3}{\sqrt{1 - (3x)^2}} = -\frac{3}{\sqrt{1 - 9x^2}} \] This implies: \[ dx = -\frac{\sqrt{1 - 9x^2}}{3} dt \] ### Step 2: Express \( x \) in terms of \( t \) From the substitution \( t = \cos^{-1}(3x) \), we can express \( x \) as: \[ x = \frac{1}{3} \cos(t) \] ### Step 3: Rewrite the integral Substituting \( x \) and \( dx \) into the integral: \[ I = \int \frac{\frac{1}{3} \cos(t) + t^2}{\sqrt{1 - 9\left(\frac{1}{3} \cos(t)\right)^2}} \left(-\frac{\sqrt{1 - 9\left(\frac{1}{3} \cos(t)\right)^2}}{3}\right) dt \] Simplifying the square root: \[ \sqrt{1 - 9\left(\frac{1}{3} \cos(t)\right)^2} = \sqrt{1 - \cos^2(t)} = \sin(t) \] Thus, the integral becomes: \[ I = -\frac{1}{9} \int \left(\frac{1}{3} \cos(t) + t^2\right) \sin(t) \, dt \] ### Step 4: Break the integral into parts Now we can break this integral into two parts: \[ I = -\frac{1}{27} \int \cos(t) \sin(t) \, dt - \frac{1}{9} \int t^2 \sin(t) \, dt \] ### Step 5: Solve the integrals 1. The integral \( \int \cos(t) \sin(t) \, dt = \frac{1}{2} \sin^2(t) \). 2. The integral \( \int t^2 \sin(t) \, dt \) can be solved using integration by parts. After solving these integrals, we will substitute back \( t = \cos^{-1}(3x) \) to express everything in terms of \( x \). ### Step 6: Final expression After evaluating the integrals and simplifying, we will arrive at: \[ I = -\frac{1}{9} \sqrt{1 - 9x^2} - \frac{1}{9} (\cos^{-1}(3x))^3 + C \] ### Step 7: Compare with given form The integral is given in the form: \[ I = \frac{1}{k_1} \sqrt{1 - 9x^2} + (\cos^{-1}(3x))^{k_2} + C \] Comparing coefficients, we find: - \( k_1 = 9 \) - \( k_2 = 3 \) ### Step 8: Calculate \( k_1^2 + k_2^2 \) Now, we need to find: \[ k_1^2 + k_2^2 = 9^2 + 3^2 = 81 + 9 = 90 \] Thus, the final answer is: \[ \boxed{90} \]
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VIKAS GUPTA (BLACK BOOK) ENGLISH-INDEFINITE AND DEFINITE INTEGRATION-EXERCISE (SUBJECTIVE TYPE PROBLEMS)
  1. int (x+ ( cos^(-1)3x )^(2))/(sqrt(1-9x ^(2)))dx = (1)/(k (1)) ( sqrt(1...

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  2. If int (0)^(oo) (x ^(3))/((a ^(2)+ x ^(2)))dx = (1)/(ka ^(6)), then fi...

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  3. Let f (x) = x cos x, x in [(3pi)/(2), 2pi] and g (x) be its inverse. ...

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  4. If int (x ^(6) +x ^(4)+x^(2)) sqrt(2x ^(4) +3x ^(2)+6) dx = ((ax ^(6) ...

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  5. If the value of the definite integral int ^(-1) ^(1) cos ^(-1) ((1)/(s...

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  6. The value of int (tan x )/(tan ^(2) x + tan x+1)dx =x -(2)/(sqrtA) tan...

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  7. Let int (0)^(1) (4x ^(3) (1+(x ^(4)) ^(2010)))/((1+x^(4))^(2012))dx = ...

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  8. Let int ( 1) ^(sqrt5)(x ^(2x ^(2)+1) +ln "("x ^(2x ^(2x ^(2)+1))")")dx...

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  9. If int (dx )/(cos ^(3) x-sin ^(3))=A tan ^(-1) (f (x)) +bln |(sqrt2+f ...

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  10. Find the value of |a| for which the area of triangle included between ...

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  11. Let I = int (0) ^(pi) x ^(6) (pi-x) ^(8)dx, then (pi ^(15))/((""^(15) ...

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  12. If I = int (0) ^(100) (sqrtx)dx, then the value of (9I)/(155) is:

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  13. Let I(n) = int (0)^(pi) (sin (n + (1)/(2))x )/(sin ((x)/(2)))dx where ...

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  14. If M be the maximum value of 72 int (0) ^(y) sqrt(x ^(4) +(y-y^(2))^(2...

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  15. Find the number points where f (theta) = int (-1)^(1) (sin theta dx )/...

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  16. underset(nrarroo)lim[(1)/(sqrtn)+(1)/(sqrt(2n))+(1)/(sqrt(3n))+...+(1)...

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  17. The maximum value of int (-pi//2) ^(2pi//2) sin x. f (x) dx, subject t...

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  18. Given a function g, continous everywhere such that g (1)=5 and int (0)...

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  19. If f (n)= 1/pi int (0) ^(pi//2) (sin ^(2) (n theta) d theta)/(sin ^(2)...

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  20. Let f (2-x) =f (2+xand f (4-x )= f (4+x). Function f (x) satisfies int...

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