Answer:
Step-by-step explanation:
1 - 2 + 10 o lw. First find a common denominator. 3 * 5. After cross reducing, multiply across ... Divide the fraction to get a decimal answer. 21 into a an. Jinit. 5 = 1.25 ... 3 = -x +8. -8 = -8. = -5 = -X. =-1(-5) = -x (-1). = 5 = x. Set up a ratio, and cross ... Combine like terms, and solve for x. Divide both sides by 2. = x= 20. = 5-1">4.
T=-1
sinA=sin(π/2-3A), A=2nπ+π/2-3A, 4A=2nπ+π/2, A=nπ/2+π/8 where n is an integer.
Also, π-A=2nπ+π/2-3A, 2A=2nπ-π/2, A=nπ-π/4.
The hard way:
cos3A=cos(2A+A)=cos(2A)cosA-sin(2A)sinA.
Let s=sinA and c=cosA, then s²+c²=1.
cos3A=(2c²-1)c-2c(1-c²)=c(4c²-3).
s=c(4c²-3) is the original equation.
Let t=tanA=s/c, then c²=1/(1+t²).
t=4c²-3=4/(1+t²)-3=(4-3-3t²)/(1+t²)=(1-3t²)/(1+t²).
So t+t³=1-3t², t³+3t²+t-1=0=(t+1)(t²+2t-1).
So t=-1 is a solution.
t²+2t-1=0 is a solution, t²+2t+1-1-1=0=(t+1)²-2, so t=-1+√2 and t=-1-√2 are solutions.
Therefore tanA=-1, -1+√2, -1-√2 are the three solutions from which:
A=-π/4, π/8, -3π/8 radians and these values +2πn where n is an integer.
Replacing π by 180° converts the solutions to degrees.
51.65 to the nearest whole number
After the whole number 51, the next digit is 6, and since this is more than 5. So we round up the 51 to 52.
51.65 ≈ 52 to the nearest whole number.
The value in the 10 digits place is 6, because the tenths place is like a centimeter, and the digit in the hundreds place, is 6 again, because it is 10 times greater than the tenths place.
