Check the picture below, that's the "inscribed angle theorem"
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Define x :
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Let the smallest number be x.
The other two numbers will be x + 1 and x + 2.
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Construct Equation :
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Sum of these numbers is 72
⇒ x + x + 1 + x + 2 = 72
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Solve for x :
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x + x + 1 + x + 2 = 72
3x + 3 = 72
3x = 69
x = 23
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Find the numbers :
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1st number = x = 23
2nd number = x + 1 = 23 + 1 = 24
3rd number = x + 2 = 23 + 2 = 25
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Answer : The numbers are 23, 24 and 25.
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F(-5) = 6(-5)^3 + 24(-5)^2 - 24(-5) + 5 = 0
so x = -5 is one zero.
Remember
i²=-1 so
i³=-i
i⁴=1
so
5i⁴+2i³+8i²-4
5(1)+2(-i)+8(-1)-4
5-2i-8-4
-7-2i is the form
cups