$$\text { Find the exact value of the limit of the sequence defined by } a _ { 1 } = \sqrt { 4 } , a _ { n + 1 } = \sqrt { 4 + a _ { n } } \text {. }$$

Short Answer

$$\text { Find the exact value of the limit of the sequence defined by } a _ { 1 } = \sqrt { 4 } , a _ { n + 1 } = \sqrt { 4 + a _ { n } } \text {. }$$