Question

If $tn=\{\begin{array}{cc}{n}^2& \text{,When n is even}\\ & \\ n^2+1& \text{,When n is odd}\end{array}$
find $t_{15}-t_{10}$

• A. 116
• B. 126
• C. 106
• D. 226

Answer 1

The correct option is B 126

$t_{10}={10}^2=100$
$t_{15}={\left(15\right)}^2+1=226$
$\therefore$$t_{15}-t_{10}=226-100=126$