Question

Use suitable identies to find the following products : i) ( x-2) ( x-2)
ii) (x+8) (x+10)
iii) (x+3)(x+3)
iv) ( x²-1/2)(x²+1/2)
v) ( 5x-3)(5x+3)
vi) (1-8x)(1+8x)
vii) (x-3)(x+5)​

Answer 1

Answer:

$1) \: (x - 2)(x - 2)$

$= {x}^{2} + {2}^{2} - 2 \times x \times 2$

$= {x}^{2} + 4 - 4x$

2) (x+8)(x+10)

=x²+(8+10)x+8×10

=x²+18x+80

3) (x+3)(x+3)

=x²+(3)²+2×x×3

=x²+9+6x

$4)( {x}^{2} - \frac{1}{2} )( {x}^{2} + \frac{1}{2} )$

$=( { {x}^{2} })^{2} - (\frac{1}{2} {})^{2}$

$= {x}^{4} - \frac{1}{4}$

5) (5x-3)(5x+3)

=(5x)²-(3)²

=25x²-9

6) (1-8x)(1+8x)

=(1)²-(8x)²

=1-64x²

7) (x-3)(x+5)

=x²+(-3+5)x +(-3)5

=x²+2x-15