Answer:
tan²x + 1 = sec²x is identity
Step-by-step explanation:
* Lets explain how to find this identity
∵ sin²x + cos²x = 1 ⇒ identity
- Divide both sides by cos²x
∵ sin x ÷ cos x = tan x
∴ sin²x ÷ cos²x = tan²x
- Lets find the second term
∵ cos²x ÷ cos²x = 1
- Remember that the inverse of cos x is sec x
∵ sec x = 1/cos x
∴ sec²x = 1/cos²x
- Lets write the equation
∴ tan²x + 1 = 1/cos²x
∵ 1/cos²x = sec²x
∴ than²x + 1 = sec²x
- So we use the first identity sin²x + cos²x = 1 to prove that
tan²x + 1 = sec²x
∴ tan²x + 1 = sec²x is identity
No the product will be less than 9/10.
This can be easily seen if the fractions are converted into decimals.
The decimal form of the product of 7/8 and 9/10 is 0.867 while the decimal form of 9/10 is 0.9. Therefore, the product of 7/8 and 9/10 is not greater than 9/10
Answer:
Profit = Rs 100
Profit %age = 6.25%
Step-by-step explanation:
Cost Price = Rs 80
Cost Price for 20 kg = Rs 1600
Selling Price = Rs 85
<u><em>Profit for 1 kg</em></u> = Rs 85 - Rs 80
=> Rs 5 (For 1 Kg)
<u><em>Profit for 20 kg:</em></u>
=> Rs 5*20
=> Rs 100
<u><em>Now Profit %age:</em></u>
=> 
=> 0.0625 * 100
=> 6.25%
Answer:
308 cm³
Step-by-step explanation:
The volume (V) of a rectangular prism ( cuboid ) is
V = lbh ( l is the length, b the breadth and h the height )
Here l = 11, b = 7 and h = 4, thus
V = 11 × 7 × 4 = 308 cm³
X - the number
The number is <span>14.</span>
