Algebra
-
If a = 1 , find the value of the expression (2a − 5b) b 2 (5a + 3b)
-
View Hint View Answer Discuss in Forum
a = 1 b 2 
= 2 × 1 − 5 2 5 × 1 + 3 2 = 1 − 5 = − 4 × 2 5 + 3 5 + 6 2 −8 11 Correct Option: C
a = 1 b 2 = 2 × 1 − 5 2 5 × 1 + 3 2 = 1 − 5 = − 4 × 2 5 + 3 5 + 6 2 −8 11
-
If a + 1 = 1 and b + 1 = 1 then c + 1 is equal to : b c a
-
View Hint View Answer Discuss in Forum
a + 1 = 1 b ⇒ a = 1 – 1 = b − 1 b b ∴ 1 = b a b − 1 Again, b + 1 = 1 c ⇒ 1 = 1 – b c ⇒ c = 1 1 – b ∴ c + 1 = 1 + b a 1 – b b − 1 = 1 − b = 1 – b = 1 1 – b 1 – b 1 – b Correct Option: A
a + 1 = 1 b ⇒ a = 1 – 1 = b − 1 b b ∴ 1 = b a b − 1 Again, b + 1 = 1 c ⇒ 1 = 1 – b c ⇒ c = 1 1 – b ∴ c + 1 = 1 + b a 1 – b b − 1 = 1 − b = 1 – b = 1 1 – b 1 – b 1 – b
-
The value of a + b is a − b b − a
-
View Hint View Answer Discuss in Forum
Expression = a + b a − b b − a = a − b a − b a − b = a − b = 1 a − b Correct Option: D
Expression = a + b a − b b − a = a − b a − b a − b = a − b = 1 a − b
-
If 2x + 1 =1, then the value of x2 + 1 is 4x 64x2
-
View Hint View Answer Discuss in Forum
2x + 1 = 1 4x
On dividing by 2, we getx + 1 = 1 8x 2
On squaring both sides, we get
x + 1 
2 = 1 8x 4 ⇒ x2 + 1 + 2 × x × 1 = 1 64x2 8x 4 ⇒ x2 + 1 + 1 = 1 64x2 4 4 ⇒ x2 + 1 = 1 − 1 = 0 64x2 4 4 Correct Option: A
2x + 1 = 1 4x
On dividing by 2, we getx + 1 = 1 8x 2
On squaring both sides, we getx + 1 2 = 1 8x 4 ⇒ x2 + 1 + 2 × x × 1 = 1 64x2 8x 4 ⇒ x2 + 1 + 1 = 1 64x2 4 4 ⇒ x2 + 1 = 1 − 1 = 0 64x2 4 4
-
If a + b + c = 2c, find a + c . a − c b − c
-
View Hint View Answer Discuss in Forum
a + b = 2c
⇒ a – c = c – b∴ a + c a − c b − c = a + c c – b b − c = a − c c – b c – b = a − c = c – b = 1 c – b c – b Correct Option: B
a + b = 2c
⇒ a – c = c – b∴ a + c a − c b − c = a + c c – b b − c = a − c c – b c – b = a − c = c – b = 1 c – b c – b
