Question

Write the coefficient of y in the expansion of (5 – y)2.

Answer 1

■ GIVEN THAT:-

$(5 - y) ^{2}$

■ SOLUTION;-

By using Identity ,

$(x - y)^{2} = {x}^{2} - 2xy + {y}^{2}$

So ,now

$(5 - y) ^{2} = (5 )^{2} - 2 \times 5 \times y + ( {y})^{2}$

$= 25 - 10y + {y}^{2}$

THERFORE, THE COEFFICIENT OF Y IS -10 .