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The sum of the coefficients of the first 50 terms in the binomial expansion of (1−x)100 is equal to:
- A.
−101C50
- B.
99C49
- C.
100C50
Explanation
Solution:
Binomial expansion (1−x)n=∑r=0n(−1)rnCrxr mein coefficients ka sum nikalne ke liye hum property ka prayog karte hain:
r=0∑k(−1)rnCr=(−1)kn−1Ck
Yahan n=100 hai aur humein pehle 50 terms ka sum chahiye, yani r=0 se r=49 tak:
Formula mein values rakhne par (k=49):
S=(−1)49100−1C49=−99C49
Sahi Answer: (4) −99C49
Explanation
Solution:
Binomial expansion (1−x)n=∑r=0n(−1)rnCrxr mein coefficients ka sum nikalne ke liye hum property ka prayog karte hain:
r=0∑k(−1)rnCr=(−1)kn−1Ck
Yahan n=100 hai aur humein pehle 50 terms ka sum chahiye, yani r=0 se r=49 tak:
Formula mein values rakhne par (k=49):
S=(−1)49100−1C49=−99C49
Sahi Answer: (4) −99C49