Simplify each sum or difference. State any restrictions on the variables.
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Answer:
2(d-2)/(2d+1) or 1 - 5/(2d+1)
d can not be -½
Step-by-step explanation:
(d-3)/(2d+1) + (d-1)/(2d+1)
Lcm: 2d+1
(d-3+d-1)/(2d+1)
= (2d-4)/(2d+1)
= 2(d-2)/(2d+1)
If further simplification required:
= (2d-4)/(2d+1)
= (2d+1-5)/(2d+1)
= (2d+1)/(2d+1) - 5/(2d+1)
= 1 - 5/(2d+1)
2d+1 = 0
When d = -½
So d can not be -½ because when the denominator becomes 0, fraction becomes undefined