Question

if a-b =6 and a square + b square =42, find the value of ab​

Answer 1

Answer:

Answer

Acceleration = - 1 m/s²

Option (1)

\orange{\bigstar}★ Given \green{\bigstar}★

Initial velocity of a car is 10 m/s

Final velocity of the car is 0 m/s

Distance travelled by the car is 50 m

\orange{\bigstar}★ To Find \green{\bigstar}★

Acceleration of the car

\orange{\bigstar}★ Formula Applied \green{\bigstar}★

3rd equation of motion

→ v² - u² = 2as

where ,

v denotes final velocity

u denotes initial velocity

a denotes acceleration

s denotes distance / displacement

\orange{\bigstar}★ Solution \green{\bigstar}★

Initial velocity , u = 10 m/s

Final velocity , v = 0 m/s

Distance , s = 50 m

Acceleration , a = ? m/s²

Apply formula ,

⇒ v² - u² = 2as

⇒ (0)² - (10)² = 2a(50)

⇒ 0 - 100 = 100a

⇒ 100a = - 100

⇒ a = - 1 m/s²

Note : Negative sign of acceleration denotes retardation

__________________________

Answer 2

Step-by-step explanation:

Given

a - b = 6

a²+ b² = 42

To find

The value of 'ab'

We know that,

$\small{\red{\underline{\boxed{\bf{(a \: - </p><p>\: b)² \: = \: a² \: + \: b² - \: 2ab}}}}</p><p>}$

given, a - b = 6 , a²+ b² = 42

Substituting the values,

(6)² = 42 - 2ab

36 = 42 - 2ab

2ab = 42 - 36

2ab = 6

ab = $\frac{6}{2}$

ab = 3

Therefore , the value of ab = 3