# Rapper

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Lepton
1. ## Minimal Area of a Cone

A cylinder with radius r=0.75 m and height h = 1 m has to be covered by a cone. Find the minimal area for the cone. Surface Area of Cone: pi*r^2 + pi*r*L So, I figured out: H= Height of the cone R= Radius of the cone (H-1)/0.75 = H/R H=-4R/(-4R+3) To calculate L, I used the Pythagoras & substituted H from above: L = sqrt(R^2+H^2) L = sqrt(R^2+(-4R/(-4R+3)) L = (sqrt(16R^4-24R^3+25R^2)/(4R-3) I see I'm heading towards something really complicated... Could you please help me find the right way to do it? I have just started doing this.
2. ## Series/Sequences of numbers

Oh, I made a mistake, sorry... It's a(n+2) = [a(n) + a(n+1)]/2 How can I calculate a(5)?
3. ## Series/Sequences of numbers

Give an explicit form each of the terms: a(1) = 1 a(2) = 3 a(n+1) = [a(n) + a(n+1)]/2 I just started with this topic. How can I calculate what a(n) is? Should I replace a(n) by 1 and a(n+1) by 3 and divide the result by 2? Would that give me de?
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