Question

HEMISTRY
MATHEMATICS 0
of y(-25) + 3(-4) + 21(-9) is
13i (B)-13i
(C) 17i
(D)-17i​

Answer 1

Answer:

Given, AB=−13I

⇒

∣

∣

∣

∣

∣

∣

2

5

3

1

∣

∣

∣

∣

∣

∣

×

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∣

∣

∣

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∣

a

c

b

d

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∣

∣

=−13×

∣

∣

∣

∣

∣

∣

1

0

0

1

∣

∣

∣

∣

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∣

⇒

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∣

2(a)+3(c)

5(a)+1(c)

2(b)+3(d)

5(b)+1(d)

∣

∣

∣

∣

∣

∣

=

∣

∣

∣

∣

∣

∣

−13

0

0

−13

∣

∣

∣

∣

∣

∣

By comparing

⇒2a+3c=−13 --- (1)

⇒2b+3d=0 --- (2)

⇒5a+c=−13 --- (3)

⇒5b+d=0 --- (4)

Solving equations 1 and 3, we get a=−2,c=−3

Solving equations 2 and 4, we get b=0,d=0

So, a+b−c+d=−2+0+3+0=1