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2 years ago

Help meeeee please. ‼️‼️‼️‼️

Mathematics

1 answer:

KatRina [158]2 years ago

8 0

Step-by-step explanation:

look at the picture !

she has to paint actually 6 rectangles :

the 3 tops of the 3 stairs.

and the 3 vertical front boards (the front of each step of the stairs).

what is the area of these rectangles ? summing up all 6 - that is the surface area to be painted.

each top rectangle is clearly

82×19 (19 cm deep) = 1558 cm²

each front board is

82×12 (12 cm high) = 984 cm²

so, in total we have

3×1558 + 3×984 = 4674 + 2952 = 7626 cm²

as surface area to be painted.

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Andrej [43]

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3 years ago

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3 years ago

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tatiyna

Integrate indefinite integral:
$I=\int\frac{dx}{e^{2x}+3e^x+2}dx$

Solution:
1. use substitution $u=e^x$
=>
$du=e^xdx$
=>
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=>
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=>
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3 years ago

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Step-by-step explanation:

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2 years ago

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fenix001 [56]

Answer:

Step-by-step explanation:

substitute

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7 0

2 years ago