The numerator difference is (6x-2y+2y-3=2y\(3x^2+y^2\)), so division gives \(3x^2+y^2\). In exams, take out the common factor.
Step 2
Why this answer is correct
The correct answer is A. \(,3x^2+y^2,\). The numerator difference is (6x-2y+2y-3=2y\(3x^2+y^2\)), so division gives \(3x^2+y^2\). In exams, take out the common factor.
Step 3
Exam Tip
ऊपर का अंतर (6x-2y+2y-3=2y\(3x^2+y^2\)) है, इसलिए भाग देने पर \(3x^2+y^2\) मिलता है। परीक्षा में common factor निकालें।
On expansion, ((x+1)3=x-3+3x-2+3x+1) and ((x-1)3=x-3-3x-2+3x-1), so the difference is \(6x^2+2\). In exams, expand cubes carefully.
Step 2
Why this answer is correct
The correct answer is A. \(,6x^2+2,\). On expansion, ((x+1)3=x-3+3x-2+3x+1) and ((x-1)3=x-3-3x-2+3x-1), so the difference is \(6x^2+2\). In exams, expand cubes carefully.
Step 3
Exam Tip
विस्तार करने पर ((x+1)3=x-3+3x-2+3x+1) और ((x-1)3=x-3-3x-2+3x-1), इसलिए अंतर \(6x^2+2\) है। परीक्षा में cube expansion ध्यान से करें।
This matches ((a-b)\(a^2+ab+b^2\)=a-3-b-3), so the answer is \(x^3-8\). In exams, identifying the identity makes expansion faster.
Step 2
Why this answer is correct
The correct answer is A. \(,x^3-8,\). This matches ((a-b)\(a^2+ab+b^2\)=a-3-b-3), so the answer is \(x^3-8\). In exams, identifying the identity makes expansion faster.
Step 3
Exam Tip
यह ((a-b)\(a^2+ab+b^2\)=a-3-b-3) का रूप है, इसलिए उत्तर \(x^3-8\) है। परीक्षा में identity पहचानने से विस्तार जल्दी होता है।
\(\alpha+\beta=9\) and \(\alpha\beta=20\). (\alpha-3+\beta-3=\(\alpha+\beta\)3-3\alpha\beta\(\alpha+\beta\)=729-540=189).
Step 2
Why this answer is correct
The correct answer is A. (369). \(\alpha+\beta=9\) and \(\alpha\beta=20\). (\alpha-3+\beta-3=\(\alpha+\beta\)3-3\alpha\beta\(\alpha+\beta\)=729-540=189).
Step 3
Exam Tip
\(\alpha+\beta=9\) और \(\alpha\beta=20\) है। (\alpha-3+\beta-3=\(\alpha+\beta\)3-3\alpha\beta\(\alpha+\beta\)=729-540=189) नहीं बल्कि (189) होगा।