Find correct to the nearest degree, the acute angle formed by the lines y = 2x + 5 and 2y = x - 6
76∘
53∘
37∘
14∘
Correct answer is C
tanθ | = | m1 - m2
1 + m1m2 |
y = 2x + 5
m1 = 2
2y = x - 6
y | = | 1
2 |
x | - | 3 |
m2 | = | 1
2 |
tanθ | = | 2 - 12
1+2(12) |
tanθ = 32 ÷ (1+1)
tanθ = 32 ÷ 2
tanθ | = | 3
4 |
θ = tan−1(34)
θ = 36.87º
θ = 37º
Find the coefficient of x3y2 in the binomial expansion of (x-2y)5
-80
10
40
90
Correct answer is C
x3y2 in (x-2y)5
n = 5, r = 3, p = x, q = -2y
5C3 * x3 -2y2
5C3 = 5![5−3]!3!
5∗4∗3!2!3! → 5∗42
5C3 = 10
: 5C3 * x3 -2y2 = 10 * x3 4y2
40x3y2
the coefficient is 40