SOLUTION
Given the question in the image, the following are the solution steps to answer the question.
STEP 1: Write the given details
![\begin{gathered} center:(0,0) \\ radius:1 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/high-school/mp2mk8x278yfg3px6dt1b81nmqubu7ad6a.png)
STEP 2: Write the formula for equation of a circle
![\begin{gathered} (x-h)^2+(y-k)^2=r^2 \\ Where\text{ }(h,k)\text{ is the center} \\ r\text{ is the radius} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/high-school/i1ol00sfzqi7rnwj7lzi1kdhe4uqqhoylc.png)
STEP 3: Find the equation of the circle
![\begin{gathered} By\text{ substitution,} \\ (x-0)^2+(y-0)^2=1^2 \\ x^2+y^2=1^2 \\ x^2+y^2=1 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/high-school/yy0czgvfsjy1fb7094gzhertcg6c6kzdib.png)
Hence, the equation of the circle is given as:
![x^2+y^2=1^](https://img.qammunity.org/2023/formulas/mathematics/high-school/j8j42e2ry08vogekxsx07r8cyxyyaogf00.png)