<p><strong>If the sum of the coefficients of all the positive powers of x, in the Binomial expansion of <math><mrow><msup><mrow><mrow><mo>(</mo><mrow><msup><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msup><mo>+</mo><mfrac><mrow><mn>2</mn></mrow><mrow><msup><mrow><mi>x</mi></mrow><mrow><mn>5</mn></mrow></msup></mrow></mfrac></mrow><mo>)</mo></mrow></mrow><mrow><mn>7</mn></mrow></msup></mrow></math> is 939, then the sum of all the possible integral values of n is..................</strong></p>

= 939∴r=4? 7n−nr−5r=0And r = 4 thenn>203And r should not be 5∴n<252∴ possible values of n are 7, 8, 9, 10, 11, 12∴ Sum of integral value of n = 57

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Maths Class 12th Maths NCERT Exemplar Solutions Class 12th Chapter Eight Binomial Theorem

If the sum of the coefficients of all the positive powers of x, in the Binomial expansion of ${(x^{n} + \frac{2}{x^{5}})}^{7}$ is 939, then the sum of all the possible integral values of n is..................

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Payal Gupta | Contributor-Level 10

2 months ago

= 939

$∴ r = 4$

$? 7 n - n r - 5 r = 0$

And r = 4 then

$n > \frac{20}{3}$

And r should not be 5

$∴ n < \frac{25}{2}$

$∴$ possible values of n are 7, 8, 9, 10, 11, 12

$∴$ Sum of integral value of n = 57

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If the sum of the coefficients of all the positive powers of x, in the Binomial expansion of ${(x^{n} + \frac{2}{x^{5}})}^{7}$ is 939, then the sum of all the possible integral values of n is..................

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If the sum of the coefficients of all the positive powers of x, in the Binomial expansion of ${(x^{n} + \frac{2}{x^{5}})}^{7}$ is 939, then the sum of all the possible integral values of n is..................