1. (i) (x + 2y + 4z)² = x² + (2y)² + (4z)² + 2 × (x) × (2y) + 2 × (2y) × (4z) × (x) [∵ (a + b + c)² = a² + b² + c² + 2ab + 2bc + 2ca] = x² + 4y² + 16x² + 4xy + 16yz + 4zx

    (i) (x + 2y + 4z)²
    = x² + (2y)² + (4z)² + 2 × (x) × (2y) + 2 × (2y) × (4z) × (x) [∵ (a + b + c)² = a² + b² + c² + 2ab + 2bc + 2ca]
    = x² + 4y² + 16x² + 4xy + 16yz + 4zx

    See less
    • 1
  2. 3√t + t√2 = 3t^1/2 + t√2., It is in one variable but not a polynomial as it contains (t^1/2), in which power is not a whole number.

    3√t + t√2 = 3t^1/2 + t√2., It is in one variable but not a polynomial as it contains (t^1/2), in which power is not a whole number.

    See less
    • 1
  3. y + 2/y = y + 2y^-1, It is in one variable but not a polynomial as it contains (y^-1), in which power is not a whole number.

    y + 2/y = y + 2y^-1, It is in one variable but not a polynomial as it contains (y^-1), in which power is not a whole number.

    See less
    • 1