Solve b . 4h ^ 2 + 20hk + 25k ^ 2 | Equatix - Math Solver

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Example

3(r+2s)=2t-4

a⋅(b-2)=3b

3(r+2s)=2t-4

a⋅(b-2)=3b

Question

$$4 i ^ { 20 } + 20 i + 25 i ^ { 2 }$$

Evaluate

$-21+20i$

Solution Steps

Calculate $i$ to the power of $20$ and get $1$.

$$4\times 1+20i+25i^{2}$$

Multiply $4$ and $1$ to get $4$.

$$4+20i+25i^{2}$$

Calculate $i$ to the power of $2$ and get $-1$.

$$4+20i+25\left(-1\right)$$

Multiply $25$ and $-1$ to get $-25$.

$$4+20i-25$$

Do the additions.

$$-21+20i$$

Real Part

$-21$

Solution Steps

Calculate $i$ to the power of $20$ and get $1$.

$$Re(4\times 1+20i+25i^{2})$$

Multiply $4$ and $1$ to get $4$.

$$Re(4+20i+25i^{2})$$

Calculate $i$ to the power of $2$ and get $-1$.

$$Re(4+20i+25\left(-1\right))$$

Multiply $25$ and $-1$ to get $-25$.

$$Re(4+20i-25)$$

Do the additions in $4+20i-25$.

$$Re(-21+20i)$$

The real part of $-21+20i$ is $-21$.

$$-21$$