Question

Proszę o pomoc

Daje NAJ!!!!

Answer 1

1. V = abH

Pc = 2ab + 2ac + 2bc

 

V = 7*6*5 = 210cm³

Pc = 2*7*6 + 2*7*5 + 2*6*5 = 214cm²

 

2. a - kraw, podstaw

H - wysokość

 

8 = 2H

H = 4

 

a = H√3

a = 4√3

 

P = a²√3/4

P = 4√3*√3 / 4

P = 12/4 = 3

V = Pp*H

V = 3*4 = 12

 

3. d = a√2

2√2 = a√2

a = 2

 

V = a³

V = 2³ = 8

 

4. n - wysokosc

n+1 - jedna z kraw. podst.

n+2 - kolejna kraw.

d = √[a²+b²+c²]

d = √[n²+(n+1)²+(n+2)²]

5√2 = √[3n² + 6a + 5]

50 = 3n² + 6a + 5

3n² + 6n - 45 = 0

Δ = 6² - 4*3*(-45) = 36 + 540 = 576

√Δ = 24

n₁ = -6-24/6 = 3

n₂ - nei spełnia wymogów zadania

czyli kraw to : 3,4,5

 

5.  V = 7*5*5 = 175

Pc = 2*7*5+2*7*5+2*5*5 = 190

 

6. c - przekatna podstawy

a - kraw. szescianu

 

c = a√2

d² = a² + c²

(3√2)² = a² + (a√2)²

18 = 3a²

a² = 6

a = √6

 

V = a³

V = (√6)³ = 6√6

 

7. H - wysokosc

a - kraw. podst

 

a = ½d

a = 4

 

H = 4√3

 

Pp = 4²√3/4 = 4√3

 

V = Pp * H

V = 4√3 *4√3 = 48