Update

Muft Shiksha™ एक 100% Free Education Portal है 🇮🇳, जिसका उद्देश्य Class 9–12 के हर विद्यार्थी तक High-Quality Education को पूरी तरह मुफ्त पहुँचाना है। 🇮🇳 हम मानते हैं कि अच्छी शिक्षा किसी student की आर्थिक स्थिति पर निर्भर नहीं होनी चाहिए। 🇮🇳 हर विद्यार्थी को वही Quality Study Material, MCQs, Quizzes, Exam Preparation, Concept-Based Learning और Bilingual Support मिलना चाहिए, जो आमतौर पर महंगी Coaching या Premium Platforms में मिलता है। Muft Shiksha™ 🇮🇳 इसी सोच के साथ बनाया गया है

Subjects
0 reads0 ratings0 helpful

Let \(S_n\) denote the sum of the first n natural numbers. Which number does \(S_n-S_{n-1}\) represent?

Answer and explanation

Correct answer: \(n\)

\(S_n=1+2+\cdots+(n-1)+n\), while \(S_{n-1}=1+2+\cdots+(n-1)\). On subtraction, the common terms cancel and only \(n\) remains. \(2n-1\) is associated with odd-number patterns. Exam tip: write consecutive sums before subtracting.

Related tags

Natural NumbersSum Of N TermsSequencesProgressionsAlgebraic ReasoningSum Of First N Natural NumbersSequences And ProgressionsMathematics

Was this question useful?

No ratings yetWrite a review / Rate this question

Student Reviews

No published reviews yet.

Add Muft Shiksha to your Home Screen

In Safari, tap Share, then Add to Home Screen.