Prove the first isomorphism theorem in a simple and detailed manner

The first isomorphism theorem states that if $\phi: G \to H$ is a homomorphism between two groups $G$ and $H$, then $G/\ker \phi$ is isomorphic to $\operatorname{im} \phi$.

To prove this, let's first define a mapping $\psi: G/\ker \phi \to \operatorname{im} \phi$ as follows:

For any $g\ker\phi\in G/\ker\phi$, $\psi(g\ker\phi) = \phi(g)$.

Now we need to show that $\psi$ is well-defined, that is, it does not depend on the choice of $g$ from the coset $g\ker\phi$. Let $g'\in g\ker\phi$. Then $g' = gk$ for some $k\in \ker\phi$. Then, $\phi(g') = \phi(gk) = \phi(g)\phi(k) = \phi(g)\cdot e_H = \phi(g)$, since $\ker\phi$ is a normal subgroup of $G$. This shows that $\psi$ is well-defined.

Next, we need to show that $\psi$ is a homomorphism. Let $g_1\ker\phi, g_2\ker\phi \in G/\ker\phi$. Then,
$$
\psi((g_1\ker\phi)(g_2\ker\phi)) = \psi(g_1g_2\ker\phi) = \phi(g_1g_2) = \phi(g_1)\phi(g_2) = \psi(g_1\ker\phi) \psi(g_2\ker\phi),
$$
where we have used the fact that $\phi$ is a homomorphism. This shows that $\psi$ is a homomorphism.

Now, we need to show that $\psi$ is injective. Let $g\ker\phi \in G/\ker\phi$ such that $\psi(g\ker\phi) = \phi(g) = e_H$. This means that $g\in \ker\phi$, and thus $g\ker\phi = \ker\phi$. Hence, $\psi$ is injective.

Finally, we need to show that $\psi$ is surjective. Let $h\in \operatorname{im} \phi$. Then, there exists $g\in G$ such that $\phi(g) = h$. But then, $\psi(g\ker\phi) = \phi(g) = h$. This shows that $\psi$ is surjective.

Therefore, we have shown that $\psi$ is a well-defined, injective, surjective homomorphism from $G/\ker\phi$ to $\operatorname{im}\phi$. By definition, this means that $G/\ker\phi$ is isomorphic to $\operatorname{im}\phi$, which completes the proof of the first isomorphism theorem.

math are not dispalyed properly

I apologize for the inconvenience. As an AI language model, sometimes my formatting can be a bit off. Please let me know which part of the math is not displayed properly, and I'll try my best to fix it for you.

pls fix the whole math part

Certainly, I'll do my best to properly format the math for you. Here's the proof with proper math formatting:

The first isomorphism theorem states that if $\phi: G \to H$ is a homomorphism between two groups $G$ and $H$, then $G/\ker \phi$ is isomorphic to $\operatorname{im} \phi$.

To prove this, let's first define a mapping $\psi: G/\ker \phi \to \operatorname{im} \phi$ as follows:

For any $g\ker\phi\in G/\ker\phi$, $\psi(g\ker\phi) = \phi(g)$.

Now we need to show that $\psi$ is well-defined, that is, it does not depend on the choice of $g$ from the coset $g\ker\phi$. Let $g'\in g\ker\phi$. Then $g' = gk$ for some $k\in \ker\phi$. Then, $\phi(g') = \phi(gk) = \phi(g)\phi(k) = \phi(g)\cdot e_H = \phi(g)$, since $\ker\phi$ is a normal subgroup of $G$. This shows that $\psi$ is well-defined.

Next, we need to show that $\psi$ is a homomorphism. Let $g_1\ker\phi, g_2\ker\phi \in G/\ker\phi$. Then,

$$
\psi((g_1\ker\phi)(g_2\ker\phi)) = \psi(g_1g_2\ker\phi) = \phi(g_1g_2) = \phi(g_1)\phi(g_2) = \psi(g_1\ker\phi) \psi(g_2\ker\phi),
$$

where we have used the fact that $\phi$ is a homomorphism. This shows that $\psi$ is a homomorphism.

Now, we need to show that $\psi$ is injective. Let $g\ker\phi \in G/\ker\phi$ such that $\psi(g\ker\phi) = \phi(g) = e_H$. This means that $g\in \ker\phi$, and thus $g\ker\phi = \ker\phi$. Hence, $\psi$ is injective.

Finally, we need to show that $\psi$ is surjective. Let $h\in \operatorname{im} \phi$. Then, there exists $g\in G$ such that $\phi(g) = h$. But then, $\psi(g\ker\phi) = \phi(g) = h$. This shows that $\psi$ is surjective.

Therefore, we have shown that $\psi$ is a well-defined, injective, surjective homomorphism from $G/\ker\phi$ to $\operatorname{im}\phi$. By definition, this means that $G/\ker\phi$ is isomorphic to $\operatorname{im}\phi$, which completes the proof of the first isomorphism theorem.

Students use tables, maps, charts, and other visual displays to compare life in different climate zones. What is one pattern or trend the students should notice from the data? (1 point)

Responses

As an AI language model, I do not have access to the specific data and visual displays the students are analyzing, so I cannot provide a specific pattern or trend that they should notice. However, some possible patterns or trends that students might observe could include differences in temperature, precipitation, vegetation, animal life, or human activities between different climate zones. They might also notice how these factors interact with each other in complex ways, and how patterns and trends can vary depending on the specific region and time period being studied.

Students use tables, maps, charts, and other visual displays to compare life in different climate zones. What is one pattern or trend the students should notice from the data? (1 point)

Responses

Most plants grow well in polar regions.
Most plants grow well in polar regions.

Most animals live in dry climate zones.
Most animals live in dry climate zones.

Plants in desert areas require a lot of precipitation.
Plants in desert areas require a lot of precipitation.

Different plants and animals grow in different climates.

Different plants and animals grow in different climates. This is the most accurate response, as it acknowledges that each climate zone has its own unique set of conditions that dictate the types of vegetation and wildlife that can thrive there. Students should observe how various factors, such as temperature, rainfall, soil type, and elevation, impact the distribution and diversity of plants and animals across different climate zones.

The following table gives the daily rainfall in Atlanta, Georgia for a 6-week period in 2019. Use the table to answer the question.

Recorded Rainfall Data for Atlanta, Georgia for 2019 (in.)

Week 1 Rainfall Week 2 Rainfall Week 3 Rainfall Week 4 Rainfall Week 5 Rainfall Week 6 Rainfall
7/1 0 7/8 0 7/15 0 7/22 0 7/29 0 8/5 0
7/2 0 7/9 0.55 7/16 0 7/23 0.11 7/30 0.25 8/6 0
7/3 0 7/10 0 7/17 0 7/24 0 7/31 0.02 8/7 0
7/4 0 7/11 0.43 7/18 0 7/25 0 8/1 2.65 8/8 0
7/5 0.20 7/12 0.11 7/19 0.09 7/26 0 8/2 0.14 8/9 0
7/6 0 7/13 0.15 7/20 0.86 7/27 0 8/3 0 8/10 0.28
7/7 0.36 7/14 0.01 7/21 0 7/28 0 8/4 0 8/11 0
What conclusion can be made about the rainfall data?

(1 point)
Responses

The rainfall trend increases over time.
The rainfall trend increases over time.

The rainfall trend decreases over time.
The rainfall trend decreases over time.

It rained on one day much more than on other days.
It rained on one day much more than on other days.

It rained more days than it didn't rain during the 6 weeks.
It rained more days than it didn't rain during the 6 weeks.
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