Simplify 7p³ + 2m³ - 6m³ + 4p - 9p + 6p³

a) -4m³ + 8p²

b) 8p² - 4

c) 4m³ - 13p³ + 5p

d) -4m³ + 13p³ - 5p

solution:

→c= a b , that is product of a and b is possible only when when a is m × n matrix and b is n × p matrix.

that is, number of columns of a= number of rows of b.

so, size of matrix , c= a b is , if a = (m × n)matrix

b= (n × p)matrix

then a b = [ (m × n)matrix] ×[   (n × p)matrix ]

→→c= a b= [m × p ] matrix

→→size of product a b will be equal to = number of rows of a × number of columns of b