How do you evaluate #((8), (5))# using Pascal's triangle?

2 Answers
Feb 26, 2017

Answer:

#56#

Explanation:

#"by definition "((n),(r))=(n!)/(r!(n-r)!)#

#((8),(5))=(8!)/(5!(8-5)!)#

#=(8!)/(5!xx3!)=(8xx7xx6xxcancel(5!))/(cancel(5!)xx3!)#

#=(8xx7xxcancel(6))/cancel(3!)#

#=56#

Feb 26, 2017

Answer:

#56#

Explanation:

enter image source here

#((8),(5))" represents 8th row , 5th column"#

From Pascal's triangle the entry in the 8th row / 5th column is

#((8),(5))=56#

#"8th row "rarr1 color(white)(x)8color(white)(x) 28color(white)(x) 56color(white)() color(white)(x)70color(white)(x)color(red)(56)color(white)(x)28color(white)(x)8color(white)(x)1#

#color(white)(xxxxxxxxxxxxxxxxxxx)uarr#

#color(white)(xxxxxxxxxxxxxxxxxx)"5th column"#