determine-the-exact-value-of-the-expression-without-using-a-calculatorcos2arctan

Question

Determine the exact value of the expression without using a calculator.

$\cos\left(2\arctan\frac{84}{13}\right)$

Accepted Answer

$-\frac{6887}{7225}$

Answer

$-\frac{6887}{7225}$

Answer

$-\frac{6887}{7225}$

Answer

$-\frac{6887}{7225}$

Determine the exact value of the expression without using a calculator.cos(2arctan8413)\(\cos\]\left\)(2\(\arctan\[\frac{84}{13}\]\right\))cos(2arctan1384)