simplify (4-8i)(2-7i)?

Question

2. 27^-(2/3)3. i^314. (-8+8i)-(5-4i)5. (x^2/3)^(4/5) thanx a bunch im sooo lost

Lavinia Carroll · Accepted Answer

(4-8i)(2-7i) = 8-56 – 16i – 28i = -48-44i

Lavinia Carroll · Answer

1. First multiply them together the same way you would multiply any two binomials, multiply 4 and 2, and 4 and -7i, then multiply -8i and 2, and -8i and -7i8 – 28i – 16i + 56i^2combine – 28i and -16i, and remember i = sq. rt. of -1, so i^2 = -1 8 – 44i – 56combine 8 and -56-48 – 44i2. 27^-(2/3)The negative exponent simply puts the number 27^(2/3) (no more negative exponent) as the denominator of a unit fraction (1 as the numerator) so 1/(27^(2/3))break up the 2/3 into (27^(1/3))^227^(1/3) = cube root of 27 = 3so 3^2 = 9so the whole thing put together is 1/93. i^31since i = sq.rt.(-1)i^2 = -1going further, if you square that again, so i^4 (or (-1)^2) = 1i^31 = i^28 * i^3 (since 28 is the highest multiple of 4, the first 28 i’s that you multiply together end up giving you 1.so, 1 * i^3 = i^3 but i^2 = -1 so i^3 = -1i-1i is the simplified answer.4. just a subtraction/distribution problem, you have to distribute the minus sign, -8 – 5 and 8i – (-4i)-13 + 12i5. (x^2/3)^(4/5)and exponent of and exponent, means you can just multiply the exponents together,2/3 * 4/5 = 8/15so, x^(8/15)

Lavinia Carroll · Answer

1) Multiply the terms using F.O.I.L. (First, Outer, Inner, Last), and know that √-1 = i( 4 – 8i ) ( 2 – 7i )= 4×2 + 4x-7i + -8ix2 + -8i x -7i= 8 – 28i -16i + 56i²= 8 – 44i + 56(√-1)²= 8 – 44i + 56x-1= 8 – 44i – 56= -48 – 44i2) 27^-(2/3)Anything to the power of a negative number is the same as one over the same number to the positive power:= 1 / 27^(2/3)= 1 / 27^(2 * ⅓)= 1 / (27^2 ^ ⅓)= 1 / (729 ^ ⅓)Anything to the power of a fraction is a root. To the power ½ is a square root; to the power ⅓ is a cube root.= 1 / ∛729= 1 / 93) i=√-1That means that i² = (√-1)² = -1That means that i⁴= (√-1)⁴ = (-1)² = 1i^31 = i^(4*7+2+1) = i^(4*7)i²i¹ = i^4^7 i² i¹ = 1^7 x -1 x i = 1 x -i = -i4) Expand:= -8 + 8i -5 + 4i= -13 + 12i5) If you raise a power to another power, you can simply multiply the exponents together:x ^ 2/3 ^ 4/5= x ^ [ (2*4)/(3*5) ]= x ^ 8/15

Lavinia Carroll · Answer

just foil as you would normally, keeping in mind that i^2 = -1.so:(4 – 8 i ) (2 – 7 i )firsts:4 * 2 = 8outer:4 * -7 i = -28 iinner:2 * -8 i = -16 i lasts :– 8 i * – 7 i = 56 i ^2 = – 56.so :(4-8i)(2-7i)8 – 16 i – 28 i – 56 = 8 – 44 i – 56 = – 48 – 44 i

Lavinia Carroll · Answer

The FOIL technique. First, outdoors, interior, final. in simple terms like numerous different polynomial simplification. of direction i = ?(-a million). So it is going to look like this: First outdoors interior final (4)(5) + (4)(-7i) + (3i)(5) + (3i)(-7i) = 20 – 28i +15i – 21i² = 20 – 13i + 21 = 40-one – 13i (simplified)

Lavinia Carroll · Answer

(4 – 8i)(2 – 7i)8 – 28i -16i – 5664 – 44i—————————–2. 27^(1/3) = 3 27^(2/3) = 9 27^-(2/3) = 1/9———————————–i^31 = i————————————(-8 + 8i)-(5 -4i)40 +32i -40i -+ 3272 -8i——————————

Lavinia Carroll · Answer

listen in class

Lavinia Carroll · Answer

-48-44i

Alize Kuhn

simplify (4-8i)(2-7i)?

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