level: Level 1SUMS
Questions and Answers List
ALGEBRAIC IDENTITY 1 TO 4
level questions: Level 1SUMS
| Question | Answer |
|---|---|
| (2x – 1/x)² | Solution: (i) (2x – 1/x)² [Use identity: (a – b)² = a² + b² – 2ab ] = (2x – 1/x)² = (2x)² + (1/x)² – 2 (2x)(1/x) = 4x² + 1/x² – 4 |
| (2x + y) (2x – y) | [Use identity: (a – b)(a + b) = a² – b² ] (2x + y) (2x – y) = (2x )² – (y)² = 4x² – y² |
| (a + 2b + c)² | (a + 2b + c)² = a² + (2b) ² + c² + 2a(2b) + 2ac + 2(2b)c = a² + 4b² + c² + 4ab + 2ac + 4bc |
| (2+x−2y)² | (2+x−2y)² = 2² + x² + (−2y)² + 2(2)(x) + 2(x)(−2y) + 2(2)(−2y) = 4 + x² + 4y² + 4 x − 4xy − 8y |
| (2x−y+z) ² | (2x−y+z) ² = (2x) ² + (−y) ² + (z)² + 2(2x)(−y) + 2(−y)(z) + 2(2x)(z) = 4x² + y² + z²− 4xy−2yz+4xz |
| (−2x+3y+2z) ² | = (−2x) ² + (3y) ² + ( 2z) ²+ 2(−2x)(3y)+2(3y)(2z)+2(−2x)(2z) = 4x² + 9y² + 4z² −12xy+12yz−8xz |