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3 years ago

If a vector a - b = 2c, a + b = 4c and c = 3i + 4j,find a and b

1 answer:

6 0

Ans:
a = 9i + 12j
b = 3i + 4j

Explanation:
We have two equations:

a - b = 2c --- (A)
a + b = 4c --- (B)

and two unknowns:
a = ?
b = ?

Whereas,
c = 3i + 4j

Add equations (A) and (B):
=> a - b = 2c
a + b = 4c
----------------------
2a = 6c

=> a = 3c --- (C)
Put the value of vector c in equation (C):

(C) => a = 3(3i + 4j)
=> a = 9i + 12j

Now that we have vector a, put that vector and vector c in equation (A):
(A)=> (9i + 12j) - b = 2(3i + 4j)

=> b = (9i + 12) - (6i + 8j)
=> b = 3i + 4j

Ans:
a = 9i + 12j
b = 3i + 4j

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Answer:

2(maximum), -2(minimum), -2(maximum).

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Answer:

d. 268 s

Explanation:

Constant Speed Motion

An object is said to travel at constant speed if the ratio of the distance traveled by the time taken is constant.

Expressed in a simple equation, we have:

$\displaystyle v=\frac{d}{t}$

Where

v = Speed of the object

d = Distance traveled

t = Time taken to travel d.

From the equation above, we can solve for d:

d = v . t

And we can also solve it for t:

$\displaystyle t=\frac{d}{v}$

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The closest answer is d. 268 s

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3 years ago