Definite integral

1003108205

Level: 
B
Compare the two definite integrals \( I_1=\int\limits_{-1}^1\left(x+\frac{\pi}2\right)\mathrm{d}x \) and \( I_2=\int\limits_0^{\frac{\pi}4}\mathrm{tg}\,x\cdot\cos ⁡x\,\mathrm{d}x \).
\( I_1 \) is bigger than \( I_2 \).
\( I_1 \) is smaller than \( I_2 \).
\( I_1 \) is equal to \( I_2 \).
These integrals cannot be compared.

1003108203

Level: 
B
Compare the definite integral \( I=\int\limits_0^{\frac{\pi}4}\frac{\cos⁡2b}{\cos^2⁡b}\,\mathrm{d}b \) to the number \( \frac{\pi}2 \).
\( I \) is smaller than \( \frac{\pi}2 \) by \( 1 \).
\( I \) is bigger than \( \frac{\pi}2 \) by \( 1 \).
\( I \) is equal to \( \frac{\pi}2 \).
\( I \) is smaller than \( \frac{\pi}2 \) by \( \frac{\pi}4 \).