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Please help me with my Trigonometry?
Write each expression in the standard form for a complex number, a + bi.
1. (1 + i)^5
2. (-√3+i)5
4 Answers
- King LeoLv 72 years ago
.
( 1 )
(1 + i )⁵
= ( √2 )⁵ [ cos(5 * ¼π ) + isin(5 * ¼π ) ]
= 4√2 ( -½√2 - ½i√2 )
= -4 - 4i
= -4 (1 + i )
━━━━━
( 2 )
Assuming (-√3 + i)⁵
arctan (1/(-√3) ) = -⅙π = 7π/6
(-√3 + i)⁵
= ( 2 )⁵ [ cos(5 * 7π/6 ) + isin(5 * 7π/6 ) ]
= 32 ( ½√3 - ½i )
= 16( √3 - i )
━━━━━━
- KrishnamurthyLv 72 years ago
1.
(1 + i)^5
= -4 - 4 i
2.
(-√3 + i)^5
= 27.7128129211020366964391414640939578710848840609660900488... +
16 i
- Steve ALv 72 years ago
(1 +i)^5 =
Use Pascal's triangle
1^5 + 5*1^4*i + 10*1^3*i^2 + 10*1^2*i^3 + 5*1*i^4 + i^5 =
1 + 5i -10 - 10i +5 + i =
-4 - 4i
(-√3 + i)^5 =
(-√3)^5 + 5*(-√3)^4*i + 10*(-√3)^3*i^2 + 10*(-√3)^2*i^3 + 5*(-√3)*i^4 + i^5 =
-9√3 + 45i +30√3 -30i -5√3 -i =
16√3 +14i
- ?Lv 72 years ago
(1 + i)^5 = (√2 e^(i*π/4))^5 = 4√2 e^(i*5π/4) = -4 - 4i
or
(1 + i)^5 = 1^5 + 5*1^4*i^1 + 10*1^3*i^2 + 10*1^2*i^3 + 5*1^1*i^4 + i^5 = -4 - 4i
Use either of these methods again to answer question 2.