Question
The expression 12x - x² - 20 is positive between which
values of x?Solution
ATQ,
So, 12x - x² - 20 > 0
Or, x² - 12x + 20 < 0
Or, x² - 10x - 2x + 20 < 0
Or, x(x - 10) -2(x - 10) < 0
Or, (x - 2)(x - 10) < 0
So, x = 2 or x = 10
So, the expression is positive between 2 and 10.
More No. System Questions
Simplify the following expression and find the final value:
(18 ÷ 6 of 2 + 7 of 5) ÷ 5
(1520 - 1350) ÷ (550 – 500) = ?
Simplify the following expressions and choose the correct option.
[540 ÷ (6 × 3) + 7.5 × 4] ÷ 3 = ?
(64/25)? × (125/512)?-1 = 5/8
52% of 400 + √(?) = 60% of 600 - 25% of 400
What will come in the place of question mark (?) in the given expression?
(72 × 4 – 92) ÷ 14 = ?
32% of 450 + 60% of 150 = ? × 9
82.3 × 644.7 × 723.4 × 815.85 = 72?
961 × 4 ÷ 31 – 15% of 180 = ? – 73
