alleryStart learning →The value of i⁴ⁿ⁺³ (n a positive integer) is
- −1
- −i
- 1
- i
Show answer and solution
Correct answer: B. −i
i⁴ⁿ = 1, so i⁴ⁿ⁺³ = i³ = −i.
CBSE Class 11 (Commerce) Complex Numbers — practice questions
Explore 27 free Complex Numbers questions in CBSE Class 11 (Commerce) Mathematics. Open each question or exercise to read its content, reference answers and available explanation.
Practise Complex Numbers with Quill →Complex Numbers questions and exercises with answers
Showing questions 1–27 of 27.
The value of i⁴ⁿ⁺³ (n a positive integer) isRead the answer and worked solution →The modulus of the complex number 3 + 4i isRead the answer and worked solution →The conjugate of (2 − 3i) isRead the answer and worked solution →If z = 1 + i, then z² equalsRead the answer and worked solution →The argument (principal value) of the complex number i isRead the answer and worked solution →The multiplicative inverse of (3 + 4i) isRead the answer and worked solution →For complex numbers, which relation is NOT defined?Read the answer and worked solution →The roots of x² + 1 = 0 areRead the answer and worked solution →If z = a + ib is purely imaginary, thenRead the answer and worked solution →The value of (1 + i)/(1 − i) isRead the answer and worked solution →|z₁ z₂| equalsRead the answer and worked solution →In z = a + ib, Re(z) and Im(z) areRead the answer and worked solution →The complex number i is defined by:Read the answer and worked solution →For the complex number z = 2 + 5i, Re z and Im z are:Read the answer and worked solution →The conjugate of the complex number z = 2 - 5i is:Read the answer and worked solution →If 4x + i(3x - y) = 3 + i(-6), then x and y are:Read the answer and worked solution →Compute (3 + 5i)(2 + 6i).Read the answer and worked solution →What is i^35?Read the answer and worked solution →The modulus |3 + i| equals:Read the answer and worked solution →The multiplicative inverse of z = 2 - 3i is:Read the answer and worked solution →Express (5 + √2 i)/(1 - √2 i) in the form a + ib.Read the answer and worked solution →Find the value of i^(-39).Read the answer and worked solution →Compute (5 - 3i)³.Read the answer and worked solution →If x + iy = (a + ib)/(a - ib), then x² + y² equals:Read the answer and worked solution →Identify the standard form of (-i)(2i)(-i/8)³.Read the answer and worked solution →Match each complex number partRead the answer and worked solution →Key in the power of iRead the answer and worked solution →
Worked practice questions
The modulus of the complex number 3 + 4i is
- 1
- 7
- 5
- 25
Show answer and solution
Correct answer: C. 5
|3+4i| = √(3²+4²) = √25 = 5.
The conjugate of (2 − 3i) is
- −2 + 3i
- 2 + 3i
- −2 − 3i
- 3 − 2i
Show answer and solution
Correct answer: B. 2 + 3i
The conjugate flips the sign of the imaginary part: 2 − 3i → 2 + 3i.
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