a)
\(=\left(3x-1-16\right)\left(3x-1+16\right)=\left(3x-17\right)\left(3x+15\right)\)
b)
\(=\left(5x-4-7x\right)\left(5x-4+7x\right)=\left(-2x-4\right)\left(12x-4\right)\)
c)
\(\left(2x+5-x+9\right)\left(2x+5+x-9\right)=\left(x+14\right)\left(3x-4\right)\)
d)
\(=\left(3x+1\right)^2-\left[2\left(x-2\right)\right]^2\)
\(=\left(3x+1\right)^2-\left(2x-4\right)^2\)
\(=\left(3x+1-2x+4\right)\left(3x+1+2x-4\right)\)
\(=\left(x+5\right)\left(5x-3\right)\)
e)
\(=\left[3\left(2x+3\right)\right]^2-\left[2\left(x+1\right)\right]^2\)
\(=\left(6x+9\right)^2-\left(2x+2\right)^2\)
\(=\left(6x+9-2x-2\right)\left(6x+9+2x+2\right)\)
\(=\left(4x-7\right)\left(8x+11\right)\)
f)
\(=\left(2bc\right)^2-\left(b^2+c^2-a^2\right)^2\)
\(=\left(2bc-b^2-c^2+a^2\right)\left(2bc+b^2+c^2-a^2\right)\)
a) =(3x -1-16)(3x-1 +16)
=( 3x-17)(3x+ 15)
b) =(5x- 4- 7x)(5x -4 +7x)
=(-2x-4)(12x-4)
c) =(2x+5-x-9)(2x+5+x-9)
=(x-4)(3x-4)
