Find the square of:
`2a +b`

Answer

To find the square of \(2a + b\), we can use the algebraic identity for the square of a binomial. The formula is:

\[ (x + y)^2 = x^2 + y^2 + 2xy \]

In our case, we can let \(x = 2a\) and \(y = b\). Now, let's apply the formula step by step.

### Step 1: Identify \(x\) and \(y\)
Let:
- \(x = 2a\)
- \(y = b\)

### Step 2: Apply the formula
Using the formula \((x + y)^2 = x^2 + y^2 + 2xy\):

\[ (2a + b)^2 = (2a)^2 + b^2 + 2(2a)(b) \]

### Step 3: Calculate \(x^2\)
Calculate \((2a)^2\):

\[ (2a)^2 = 4a^2 \]

### Step 4: Calculate \(y^2\)
Calculate \(b^2\):

\[ b^2 = b^2 \]

### Step 5: Calculate \(2xy\)
Calculate \(2(2a)(b)\):

\[ 2(2a)(b) = 4ab \]

### Step 6: Combine all parts
Now, combine all the parts together:

\[ (2a + b)^2 = 4a^2 + b^2 + 4ab \]

### Final Answer
Thus, the square of \(2a + b\) is:

\[ (2a + b)^2 = 4a^2 + b^2 + 4ab \]

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