lease see this one, maths

i dont have the answer

2 Answers

1.3.5.7+3.5.7.9+5.7.9.11+....+99.101.103.105

write each term as

1/10x[1.3.5.7.9 - (-1).1.3.5.7]
1/10x[3.5.7.9.11 - 1.3.5.7.9]
...
...
...
1/10x[99.101.103.105.107-97.99.101.103.105]

adding all of these, we get

1/10[99.101.103.105.107+1.3.5.7] which is option b

[1]

T_r = ((2r)²-1)((2r+4)²-1)

= (2r-1)(2r+1)(2r+3)(2r+5)

= (2r-1)(2r+1)(2r+3)(2r+5) ((2r+7)-(2r-3))10

= 110 ((2r-1)(2r+1)(2r+3)(2r+5)(2r+7) - (2r-3)(2r-1)(2r+1)(2r+3)(2r+5))

√ √ || {} [] () → ~ ^ x x x → → ln log lg lim lim cos sin tan cot arcsin arccos arctan

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