Question

(A) if x = 1 then find the value
a) 3x - 1
b) -3x² + 2x -1

(B) if x = 1 and y = -1 find the value of the following
a) x²+y²+2xy
b) x²-y²


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Answer 1

Answer:

(A) if x = 1

a) 3×1-1

=3-1

=2

b)-3×1×1+2×1-1

= -3×1+2×1-1

= -3+2×1-1

= -3+2-1

= -3 +1

= -2

B) If x=1 and y= -1

a)x×x+y×y+2×x×y

=1×1+(-1)×(-1)+2×1×(-1)

=1+1-2

=2-2

=0

b) x×x-y×y

=1×1-(-1)×(-1)

=1-1

=0