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2 years ago

Yh plss I need an answer to this question plss

Mathematics

1 answer:

VikaD [51]2 years ago

7 0

Question:

A boy makes a cone of diameter 28 cm without a base. He then cuts a smaller cone of diameter 20 cm from the cone. He used the bottom part as a lampshade. If the height of the lampshade is 11cm,

(a) find the volume of the whole cone.

(b) find in cm2, the area of the material used to make the lampshade.

Answer:

(a) V ≈ 16420.1

(b) A ≈ 2690.1 cm²

Step-by-step explanation:

<u>Solution for (a)</u>

Formula: The formula for the volume of a cone is V = 1/3 hπr².

V= πr² h /3 = π × 28/ 2 × 20/ 3 ≈ 16420.0576

16420.0576 in nearest tenths is 16420.1

Therefore, the volume of the whole cone is 16420.1 cm²

<u>Solution for (b)</u>

Formula: A = πrl + πr2.

l = r² + h²

Solving for A

A = πr (r + h²+ r²) = π × 20 × (20 + 112 + 202) ≈ 2690.80077

2690.80077 In nearest tenths, is 2690.1

Therefore, the area of the material used to make the lampshade is 2690.1 cm²

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Therefore the value of y(1)= 0.9152.

Step-by-step explanation:

According to the Euler's method

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Substituting x =0.2 and h= 0.2

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$y(0.4+0.2)\approx y(0.4)+0.2[(0.4)^2\times y(0.4)-\frac12 (y(0.4))^2]$

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$y(0.6+0.2)\approx y(0.6)+0.2[(0.6)^2\times y(0.6)-\frac12 (y(0.6))^2]$

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Substituting x =0.8 and h= 0.2

$y(0.8+0.2)\approx y(0.8)+0.2[(0.8)^2\times y(0.8)-\frac12 (y(0.8))^2]$

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Therefore the value of y(1)= 0.9152.

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3 years ago

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Yh plss I need an answer to this question plss​

Yh plss I need an answer to this question plss